Kunz On The Gem Mines of Southern California
Last Updated: 23rd Feb 2008
Kunz On The Gem Pegmatites of Southern California
As gemologist for New York City’s prestigious Tiffany & Company, George F. Kunz took a considerable interest in the discovery of gem-bearing pegmatites in southern California in the 1890’s. In 1904, he authored an extensive study of gem materials produced in California, which was published by that State’s Mining Bureau. Kunz devoted considerable space to providing a summary history of the gem pegmatites, then provided notes on some of the prolific producers and promising prospects of Pala, Mesa Grande, Coahuila, Ramona, and Jacumba districts.
The following transcription contains only that portion of Kunz’s report of gem sources in California that apply to the southern gem-pegmatites; information on other regions of the state have been left out.
– Daniel E Russell
GEM MINES IN CALIFORNIA.
By George F. Kunz
From: Kunz, George Frederick
Gems, Jewelers' Materials, and Ornamental Stones of California
Bulletin No. 37 California State Mining Bureau San Francisco, June, 1905
The second important discovery in this region was made, or at least announced, twenty years later, in 1892, by Mr. C. R. Orcutt – the great locality of lithia minerals at Pala. Some allusions to red tourmaline from uncertain sources in this part of the State had appeared before; but nothing very specific. In the list of California minerals prepared by Prof. William P. Blake in 1880-82, and also quoted in that of Mr. Henry G. Hanks, published in 1884, f references are made to the recent discovery of rubellite, for the first time in the State, associated with lepidolite, “in the San Bernardino range, southern California.” The general description is precisely that of the Pala specimens, but the location is very indefinite. Mr. Hanks refers to the same association under lepidolite, and mentions a specimen in the State Mining Bureau, from San Diego County, and remarks that “this may at some future time be found profitable to extract lithium from it” – a prediction abundantly verified now. Mr. Orcutt, however, was the first to make the locality known. It was noted by the author in his report for 1893, where the following account was given:
“Mr. Charles Russell Orcutt has announced a new and remarkable occurrence of pink tourmaline in lepidolite, similar to that of Rumford, Maine, 12 miles south of Temecula, near San Luis Rey River, in San Diego County, the southern county of California, and it has already become celebrated from the abundance and beauty of the specimens yielded, as much as twenty tons having been sent East for sale. Through San Diego County runs the Peninsula range, rising several thousand feet between the coast and the Colorado Desert. In these granite mountains are diorite intrusions and some metamorphic schists, etc. West of the summit lies a parallel belt of granitic rock characterized by dikes of pegmatite, in one of the largest of which occurs this great deposit of lepidolite with tourmaline. In Pala, a little west of Smith's Mountain, in the Peninsula range, * * * a ledge of lepidolite containing rubellite has been traced for over half a mile. It consists of a. coarse granite, penetrating a norite rock, and including masses of pegmatite. Small garnets occur in the granite, and black tourmaline, with a little green tourmaline. The lepidolite appears in the southern portion, finally forming a definite vein which at one point is twenty yards wide. The rubellite is chiefly in clusters and radiations, several inches in diameter, also occasionally as single crystals, and the specimens of deep pink tourmaline in the pale lilac mica are remarkably elegant. About eighteen tons were mined during 1892.”
The next important discovery was made six years later, in 1898; this was the wonderful Mesa Grande locality, some 20 miles southeast of Pala. There are various stories about the Indians having known it for many years, and the most familiar account is that given further on under Tourmaline. But the fact that some of the highly colored crystals are found in Indian graves in the vicinity, suggests that they may have been known and valued perhaps for a very long time. The ledge in which they occur is exposed by erosion on the side of the mountain; and the natives had certainly learned where to find crystals, and had them in their possession for some years before the whites knew anything about them. It is even said that they had learned how to do a little rude blasting, and thus to reach the cavities in which the minerals occur. It was not until 1898, however, that this now famous locality was made known to the world.
The discovery was announced in the author's report for 1900, on the production of precious stones in the United States, as follows:
“In 1898, while prospecting in Mesa Grande Mountain, San Diego County, California, for lepidolite, a large ledge was observed that appeared to be a mass of this mineral. This locality is at an altitude of 5000 feet on the Mesa Grande Mountain, a region in which no geological work had up to that time been done. The first few blasts showed that lepidolite was present in quantity, and also in larger and more brilliant scales than in the well-known locality at Pala, Cal. Both in the lepidolite and in the associated quartz there are magnificent crystals of tourmaline, and, as at Pala, the rubellite variety predominates. The new locality differs, however, in having the tourmaline in distinct, isolated crystals. Many of these are translucent, or even transparent, and occur as large, separate crystals, with perfect prisms and terminations. They differ in both these respects from the Pala crystals, which are nearly opaque and grouped in radiations almost blending into the matrix, which latter is lepidolite, with rarely ever any quartzite. The rubellite seems the predominating variety at Mesa Grande Mountain; but there is also a large proportion of parti-colored crystals – i.e., those made up of three, four, or five distinct sections, as at Haddam Neck, Conn., and Paris, Me.; others present the Brazilian type, in which several different colored tourmalines appear, as though included one within the other. In the Brazilian crystals, however, the interior is generally red, inclosed in white, and the exterior green. This concentric arrangement is reversed in the crystals from Mesa Grande Mountain, which are generally green in the interior, or yellow-green, inclosed in white, with the exterior red. The habit of the crystals is also very interesting, in that many of them, when doubly terminated, end in a flat, basal form of pyramid, and are not hemimorphic, as tourmalines generally are.”
The great Pala Chief mine, which has given its name to the middle one of the three ridges or mountains at Pala, and has yielded magnificent tourmalines and the largest and Sliest gem-spodumene crystals, was located in May, 1903, by Frank A. Salmons, John Giddens, Pedro Peiletch, and Bernardo Heriart. The actual discoverers were probably the two last named, the Basque prospectors who had already been working and locating claims with the two Sicklers, father and son, on Heriart Mountain, the ridge a little to the east. Mr. Salmons has been the principal operator, however, of this very notable mine.
The first public announcement of these discoveries appeared in the writer's report on gem-production in the United States for 1902, having been introduced late, while the report was being printed in 1903. They were also described by the writer in " Science" for August 28,1903, and in the American Journal of Science for September of the same year.
Meanwhile, on September 8,1902, gem tourmaline had been discovered on Aguanga Mountain, some 5 miles south of Oak Grove, by Mr. Bert Simmons. This locality lies nearly east from Pala and south from that at Coahuila, next to be mentioned, and about equally distant from the two, some 15 miles. Kunzite has since been found on the same claim.
On May 30, 1903, Mr. Simmons discovered both colored tourmalines and kunzite in Riverside County, some 10 miles west of the old Hamilton ( first) discovery. The locality is on Coahuila Mountain, about 20 miles northeast of Pala. The mine was for some time known as the Simmons mine, but has been sold to Mr. E. A. Fano, of San Diego, and is now called by his name. This is one of the most promising and productive mines of the region.
The discoveries at and around Ramona followed in rapid succession, in 1903. Some had been made several years earlier, but they had not attracted much notice. Essonite garnet was reported near Ramona in 1892, by D. C. Collier, and also fine epidote. Much of the essonite found hereabout is of rich color and fine gem quality. Several mines, with this "hyacinth" variety of garnet and more or less of beryl and tourmaline, were located in May, July, and September, 1903.
On October 3d of that year, topaz was discovered in the same vicinity, by James W. Booth and John D. Farley. This was a novel and important addition to the gem products of the State. The crystals are of various sizes, some of them large, often transparent, and range from colorless to pale shades of blue, much resembling those from the old and well-known locality at Sarapulka in the Ural Mountains. These minerals will be described further on, in the body of this report, * and the several mines will be enumerated, with their special products, in the section following.
As was noted before, the garnet and topaz belt seems to run on a distinct and parallel line somewhat southwest of the tourmaline-kunzite mines. The main localities are near Ramona; but if a line be drawn from that point southeast to the Mexican border, it will strike another great garnet region near Jacumba Hot Springs. These localities have only recently been much known or examined. They were first described in the writer's report on gem production for 1903, together with the Ramona discoveries above noted,* as follows: "
Essonite has been found at a number of localities in deposits spread over a considerable territory from 9 to 10 miles northeast of Jacumba Hot Springs, San Diego County, Cal., usually associated with granite and granular limestone. At three of the places some gem material has been found. Associated with it is a little vesuvianite and crystallized quartz. Eleven localities in this region are noted. Essonite has also been found near San Vicente, El Cajon Mountains, but the crystals were full of imperfections. The finest essonite crystals are obtained at Ramona, San Diego County, associated with green tourmaline, white topaz, and beryl, occasionally in perfect dodecahedrons and trapezohedrons, of rich yellow to orange-red color, and very brilliant. They have also been discovered at Warner's Ranch, Mesa Grande, Santa Ysabel, Gravilla, and Julian, San Diego County; Deer Park, Placer County; Laguna Mountains and Jacumba, and also at several places below the Mexican line. As some of the crystals were of exceptional brilliancy, it is possible that on further development many fine gems will be obtained."
The name Jacumba is used in a very general way for any place within a few miles of the store and springs. It properly belongs to a small valley surrounded by mountains of granite, and locally noted for its earthquakes and hot springs, situated close to the Mexican line. The springs are liable to great fluctuations of level, and there are extensive lava-flows among the mountains around, so that the region appears to be one of recent volcanic activity. As yet, however, it has not been accurately mapped or geologically examined. The springs are both hot and cold, variously impregnated with mineral substances, and are likely to become important as a health resort, especially as the country still abounds with wild game. They are situated on the projected railroad line skirting the frontier, from San Diego to Phoenix, Arizona-74 miles east of San Diego and some 20 miles from Campo, in the S. E. i of Sec. 12, T. 18 S., R. 7 E., S. B. M. A short distance east is the main mountain crest, and then a steep descent to the Colorado Desert.
Throughout this region around Jacumba, essonite garnet is found at various points, together with black tourmaline and some beryl. As elsewhere in all the granite country of San Diego County, these minerals are associated with pegmatite veins, though at one or two points the garnets are reported in a limestone. The mines best known are situated in the Santa Rosa Mountains, several miles northeast of Jacumba. Not much working has been done as yet, but there is likely to be a good deal more soon. One mine, the Dos Cabezas, in which the garnets occur in a marble, has been known for some ten years, and occasionally worked, yielding many fine hyacinths.
The country hereabout is very wild, rugged, and inaccessible, and wood and water are scarce. If the railroad is opened through, this may become an important region of gem-production. In the whole hilly country of the granite and diorite, west and south from these lines of opening, here briefly indicated, constant reports are coming in of interesting mineral discoveries. The orbicular diorite, or napoleonite, elsewhere described, near Dehesa, and the newly discovered lilac dumorticrite, not far from the same place, may both become valuable ornamental stones, if procurable in quantities sufficient for such purposes. These are described in the body of this report. The whole country seems" full of possibilities for precious and semi-precious minerals; and years must yet pass before it will be so fully explored that any complete estimate of its resources can be formed. Meanwhile this report brings together most of what has been discovered, and also of what has been done thus far, in regard to the gem-minerals of southern California.
Besides the references made to a number of gem mines in the body of this Bulletin, the following more specific data are here presented with reference to some of the more important ones. For the purpose of obtaining this information, a special inquiry was undertaken at the close of the last year, 1904, in behalf of the State Mining Bureau; and representatives of the Bureau visited a number of the mines and collected valuable data, which are herewith presented.
It is well to remember the fact that there is already more actual mining for gems done in the State of California than in any other State or Territory of the Union, while the indications are that there will be many more gem mines discovered in southern California as remote districts are opened and old ones more fully explored.
The following data are grouped (1) geographically, and to some extent also (2) in the order of discovery —beginning in Riverside County, and proceeding southward and southwestward, in San Diego County, by Pala, Mesa Grande, and Ramona, -to the Mexican line at Jacumba.
These are the most northern occurrences of gem tourmaline, and the earliest discoveries were made here.
Fano Kunzite-Tourmaline Mining Company – This mine consists of four claims, about 3 miles north of Coahuila Indian Reservation, Riverside County, and was located in 1902 by Bert Simmons. The nearest post office is Hemet, Riverside County. After some surface work had been done, a tunnel was started 300 feet from the summit of the hill, to cross the ledge, but by a mistake in calculation, the ledge proper was crossed about 20 feet from the surface. The parties then continued their operations until, at a depth of 176 feet, solid blue granite was readied. The tunnel was then abandoned, and work from that time has been confined to the surface. The ledge is about 5 feet in width, with a northwesterly and southeasterly strike, and a dip to the southwest of about 17 degrees. The pegmatite is finely crystallized, and resembles that of the other tourmaline and kunzite mines in southern California.
Three men are at work at present, and operations will be continued indefinitely. The output so far has been 25 pounds of kunzite, white; 1 pound of kunzite, pink; and 25 pounds of all classes of tourmaline, mostly blue and green; about 250 pounds of beryl have also been taken out, but only about five per cent of it available for gem purposes. Two hundred pounds of very fine quartz crystals also have been sold, and about a ton of lepidolite and 30 or 40 pounds of amblygonite; also splendid flake mica large enough for conmercial purposes has been discovered.
There is a spring near the property on land rented by the owners of the mine; also plenty of oak timber for mining purposes. Considerable money has been expended here without much result, but for the work actually done on gem pockets, this mine has been a splendid producer
Columbia Gem Mine – This, the oldest tourmaline mine in the State, is situated at Coahuila, Riverside County, and owned by Messrs H. C. Gordon, P. E. Johnson, J. C. Connell, and William Dyche. of San Diego; it is about half a mile northwest of the road leading from Coahuila to the Hemet reservoir, and near the summit of the divide crossed by this road. Nothing has been done on this mine, except assessment work, for over five years, but it was the first tourmaline mine discovered in southern California, and it has produced a great many beautiful gems. The pockets, however, seem to have been worked out, and nothing important has been found recently. The ledges of pegmatite are very fine granite, and both sides of the pocket material seem to be the same character, thus differing from any other mine yet found in the gem districts of California. There is no water or timber available and it is altogether a desolate region. The altitude is about 5000 feet.
Passing southward from the Coahuila region, into San Diego County, the locality next described lies by itself, about half way to the great Mesa Grande-Pala line of mines. Although not yet an important producer, he occurrence is very interesting, as suggesting other possible localities yet to lie discovered in the intervening area.
Gem Mine No. 1 – Owned by Mr. Bert Simmons, of Oak Grove, and Charles Gordon, of San Diego. Practically no work has been done on this mine since its location in June, 1903. Its altitude is higher an any other gem mine in San Diego County, being 5100 feet above a level, and about one mile east of the summit of Aguanga Mountain. 16 average width of the vein, as far as could be seen, was 4 feet, but it is badly broken, and upon examination showed that both foot and hanging walls were of very hard blue diorite. Great pressure has apparently crushed the ledge, and the pocket layer is found on the top, between the diorite and the pegmatite, and presents fine, broken crystallizations of orthoclase and albite, in which a red clay is mixed The tourmaline crystals show much indication of dynamic action, being badly broken and twisted, but afford nodules of beautiful coloring - deep blues, reds, and an almost emerald-green predominating. The mine is located on the top of the divide or watershed between San Luis Rey River and the Temecula Canon. So little work has been done that it seems better to reserve any report as to the quantity and quality until more is ascertained. Parties are at work at present on the mine.
As elsewhere described in this Bulletin, the mines near Pala are located on three hills or ridges, the western being properly called Pala Mountain, on which are the great lepidolite, or Alvarado, mine, and the Stewart mine, next described, which yields some gem material. The other mountains, Pala Chief and Heriart, which are apparently foothills or spurs of Agua Tibia Mountain, are those yielding gem spodumene as well as tourmaline. Some 18 miles to the southwest, but probably belonging to the same range of hills, lie the great tourmaline mines of Mesa Grande. These will be given in the order stated.
Stewart Mine, Pala Mountain – This mine, said to have first been discovered by an Indian deer-hunter named Vensuelada, in the early days of California history, was first worked by a miner named Henry Magee, who located the claim as a quicksilver mine, mistaking the pink tourmaline for cinnabar, but upon analysis he abandoned his prospect. Next it was located as a rock-claim by Don Tomas Alvarado, a Mexican land-owner in that locality, who believed that the beautiful bluish, pinkish, and gray minerals studded with transparent pink crystals were a peculiar variety of marble. Several years later a German scientist, who was familiar with lithia mines in Europe, saw a specimen of Pala lepidolite in a mineral collection in New York. Obtaining a piece, he made an analysis and found that this ore was as rich in lithia as any found in the world. From this time forward, gradual development under many ownerships has proved that great deposits of lithia-bearing ores exist in the pegmatites of the Pala district, the largest and most valuable being the Stewart and Alvarado mines.
In examining the workings and surface of the Stewart mine, owned by the American Lithia Company, of New York, numerous indications of gem minerals were met with, especially in the lower workings. As in the Alvarado mine, the lepidolite is generally studded with small, fan-shaped crystallizations of rubellite (pink tourmaline), with occasional crystals of bluish or greenish tourmaline, but not of gem quality. Near the surface the tourmalines are small and perfectly crystallized, but are more or less fractured, opaque, and unfit for jeweler's use. In the deeper workings and in the extreme western tunnels, however, pink tourmalines from one-half to one inch in diameter are found in columnar groups, all more or less altered, and of not over three (3) in hardness, associated with quartz, orthoclase, gray lepidolite, amblygonite. Triplite and triphylite are also associated minerals. Large crystallizations of what appears to be an altered spodumene were observed, penetrating the quartz.
On the surface, small green tourmalines were found in the pegmatite, generally more or less flattened between the cleavage planes of muscovite mica.
Several years ago a pocket containing about a quart of small tourmaline crystals was found in coarse pegmatite, 60 feet south of the present tunnel of the Stewart mine. Some of these crystals were cut into very good gems, but no further work at that spot has been done.
Pala Chief Mine – This mine was located in May, 1903, by Mr. John Giddens, Pedro Peiletch, Bernardo Heriart, and Frank A. Salmon. The main workings are at an altitude of 1220 feet (aneroid). The work consists of open cuts 250 feet wide, extending to a depth of from 10 to 30 feet horizontally on the vein, and at the deepest working the ledge is 21 feet in width vertically. A tunnel 45 feet long was run to encounter the vein up to about 20 feet depth, but it was found that the ledge was a blanket vein, and nothing was discovered in that place. But in the upper or surface workings the hanging and foot walls were both found to be of bluish and grayish decomposed diorite. The upper part of the vein consists of 3 feet of white, finely crystallized pegmatite. Beneath this the crystallizations become coarser and more granitoid. The third layer was composed partly of finely crystallized albite and orthoclase, upon the lower edge of which, and extending to the pocket, was a layer of lithia-bearing micas. In the interior of the pockets, which are generally 8 to 10 inches wide, pinkish and white talc was found, in which occurred numerous large and perfect quartz crystals with pink and white spodumene. As in most of the mines of southern California, the lower half of the ledge, below the pocket line, is a very finely crystallized granite without mica, with small crystals of essonite garnet. The above-described characteristics of the ledge are general throughout the mine. The minerals noted were spodumene, pink, lavender, and white; tourmaline, blue, green, and red; orthoclase, albite, graphic granite; lepidolite. pink, green and lavender; muscovite, quartz crystals, steatite, and other clays.
The products so far noted are tourmaline, kunzite, and quartz crystals. Giant powder was used entirely, and it was found to be the only explosive that was satisfactory. Two men have been working nearly all the time; hut during the last six months very little of the precious stones rewarded their labors. There is no water or timber on the property and the nearest water is about one mile away.
The section and township in which the mine is located were not available, but it lies east from Pala, at a distance of three miles, and the workings can be seen from the town of Pala, which is the nearest base of supplies.
Tourmaline Queen Mine – This mine, owned by Mr. Frank Salmon, John Giddens Pedro Peiletch, and Bernardo Heriart is situated near the summit of the northeast slope of Pala Chief Mountain, at an altitude of 1450 feet. It is about 3½ miles north by a little east from Pala. San Diego County. The section and quarter were not obtainable. The mine was located as a quartz claim by the ahove-named parties in March, 1903. The vein is about 14 feet wide, and dips to the southwest 15 degrees.
Very little has been done on the property, but scalping work in the nature of an open cut 60 feet wide, and entering the vein to a depth of about 10 feet, produced in weight approximately 80 pounds of gem tourmaline crystals. The colors are yellow, green of several different shades, light pink, ruby-red, and black. In examining the ledge, 18 inches lying between the diorite hanging wall and the coarse pegmatite appears to be an infiltration of decomposed feldspar, gradually altering to pegmatite. Below this are about 3 feet of coarse, granular pegmatite (or granite), consisting of crystallized quartz, feldspar, and muscovite mica, with impurities of black tourmaline in fan-shaped crystallizations, and essonite garnets (microscopic), with occasional crystals of biotite mica and hornblende. Below this again, and gradually altering from the above, are masses of graphic granite, incrusted at the lower edge with albite, in which the gem tourmaline seems to have a root or extremity. Between the albite and the line-rock (or granite) are large pockets filled with rose- and lavender-colored muscovite, and decomposed spars in the nature of a whitish or pink clay; in these pockets the gems are found, broken in many instances, and more or less altered. Many crystals were observed with an exterior of opaque green, while the interior was a rich pink or ruby-red, affording beautiful gems.
The ledge has been prospected for about 250 feet, and shows gem indications wherever it has been opened. The hanging wall is a coarse, greenish and grayish diorite, which is the general formation of the entire belt. The foot wall is the same, though showing more alteration. Both Giant and Judson powders have been used, although from the hardness and toughness of the rock, the former was found to be the best.
After the pocket material has been extracted, screens are used, by which the dirt and fine, worthless stuff are eliminated. The matter left in the screens is then examined for gems, and afterwards washed. Two of the owners have performed all the work so far accomplished, and no other men have been employed. Active operations will again be resumed, but nothing is being done at present. The same parties have filed on a spring 350 feet northeast of the present workings, and abundant water for mining and domestic purposes has been developed.
The minerals noted in above claim are: tourmaline, albite, orthoclase, muscovite, lepidolite, kaolin, talcose clays, essonite garnets, hornblende, and indications of epidote.
The lower part of the ledge is composed of a fine, granular mica-less granite, of a gray color, banded at intervals of from 3 to 6 inches with minute essonite garnets, whence the name line-rock. As is usually the case in all ledges of pegmatite bearing precious stones in this region, this lower layer of the ledge has approximately the same width as that of the formation from the pocket layer or center to the top, and lies directly in contact with the diorite foot wall.
Tourmaline King Mine – This mine is owned by F. B. Schuyler, Mrs. F. B. Schuyler, D. G. Harrington, and Mrs. H. E. Harrington, of Oceanside, Cal., and is situated on the north slope of Pala Chief Mountain, about three hundred yards from the summit, at an altitude of 1540 feet. The mine was located in March, 1903, by the above-named parties, but very little work has been done, rendering it practically impossible to make a conclusive report. The mine is 4 miles directly north of Pala, and is the last mine so far discovered at the western extremity of the Pala mineral belt.
The vein dips to the southwest at an angle of 16½ degrees. It presents an average breadth of 7 feet, and is essentially coarse pegmatite, but shows evidence of crushing and is badly broken in many places. The hanging wall is a coarse gray diorite, and at the place where the work has been done lies over about 15 inches of coarse broken feldspar and lepidolite mica. It is in this stratum that the gems appear, which is contrary to the general pocket formation of the Pala district. Tourmaline was the only gem-stone noted, and occurred in pencils, disseminated through this altered mass of decomposed spar, and apparently out of place. Concretions of albite, coated with beautiful purple muscovite, were found loose in the soil. Some quartz crystals and essonite garnets, badly shattered, were also seen in the float. The ledge at this place was too badly broken to note the exact character of the pegmatite, and the “line-rock,” or lower stratum, had not been uncovered, so that its character could not be determined. No work has been done on the property for several months, and nothing satisfactory could he rued as to when work would he resumed. About ten pounds of crystals were secured in a cut 12 feet wide, and barely scalping off the top layer of earth.
Naylor-Vanderburg Mine – This mine, also situated mar Pala, is owned by Fred M. Sickler and M. M. Sickler; altitude, 1400 feet, on the eastern slope of Mount Heriart. The location was made by Mr. Sickler in February, 1903, soon after he had discovered that the pink and white crystals which lie had found on the mountain side were not tourmalines, as they had been called, or any stone known to local mineralogists. After much trouble and expense, Mr. Sickler considered the stone of uncertain value, but continued his investigations and at length sent a piece to the writer at New York, who determined it as spodumene and after whom it was named kunzite, by Prof. Charles Baskerville, of North Carolina, as a new gem-stone to the first occurrence of transparent parent pink or lavender spodumene in the world.
The ledge at the point examined was 16 feet in width, but badly broken. At this place an open cut entering the vein to a depth of 22 feet and about 30 feet in width, has produced approximately five pounds of perfect gem stone; although several pieces have been found in adjacent workings, this seems to be the best part of the ledge.
In examination of the mine, the hanging wall is gray orbicular diorite. Between this and the ledge itself, an 18-inch layer of decomposed feldspar and clay was found as a gouge. About 7 feet of coarse granitic pegmatite forms the upper part of the ledge, altering into decomposed layers of albite and orthoclase. In this latter are small pockets, seldom larger than a man's hand, in which one or two crystals of kunzite will be found, completely covered with yellow, pink, or white clay. No metallic stains are found in the upper part of the ledge, but the lower beds of granitic rock, carrying interlineations of garnet, are in many places stained with manganese, and show large crystallizations of triplite, from which it is evident the kunzite receives its coloring. The vein has a dip of 10 degrees to the west, and extends the full length of the location, 1500 feet, joining the Caterina mine on the south.
The minerals noticed are: muscovite, pink, green, and lavender, in very large scales; montmorillonite and steatite talcs; pink, green, and white spodumene; and black tourmaline, but no gems of that stone. Albite and orthoclase, with some potash feldspars, are the mother of crystallization. It has been reported that spinel has also been discovered in this mine; associated with it were deep-colored green beryl and columbite.
There is no water or timber on the property. This mining claim is embraced within the boundaries of the Pala Indian Reservation, but was located before the reservation was declared. The output of the mine since the beginning of work has been about ten pounds of gem kunzite, no other minerals having been disposed of. Some pink and green beryls were noticed, but nothing has been developed in that line.
Other claims and openings on Mount Heriart are enumerated in the body of this Bulletin, this one being thus far the most important. The following are among the principal of these openings:
Heriart Claim – owned by F. M. and M. M. Sickler. A tunnel has been run a distance of 40 feet. A pegmatite lithia-bearing ledge was encountered, from 1½ to 4 feet in width. The ledge occurs in a granite dike, which in turn traverses the diorite. The granite dike is about 100 feet in thickness, and can be traced for over 2000 feet. The lepidolite occurs in white and lilac colors, and is often full of radiated tourmalines,
both pink and green. Large amounts of muscovite are often encased in the lepidolite. Amblygonite is also found. The tourmalines are of various shades of green, and some blue and pink crystals occur, but as yet have not been found in large quantities. Crystals of albite and orthoclase occur in the pockets. About two tons of lepidolite have been extracted from the tunnel.
San Pedro Claim – On the San Pedro claim, owned by Pedro Peiletch and Bernardo Heriart, the Naylor-Vanderburg ledge has been cut. Some kunzite, tourmaline, and beryl have been found, besides lepidolite. This ledge is exposed for nearly a mile in length. At four different points it exas been cut. exposing kunzite and lepidolite.
Caterina Mine –, owned by Bernardo Heriart ami M. M. Siekler. A cut
has been made 40 feet in length and 30 feet in width, exposing a ledge of lepidolite 2½ feet in thickness. About six tons of lepidolite have been extracted from this cut. Some kunzite and spodumene were found, the greater part of which was float. Other gems found were pink beryl and a few tourmalines.
The Mesa Grande mines are situated on the hill or mountain of that name, and are the most southern of the gem tourmaline localities in the region. The ridges stretch along northwestward to the Pala and Agua Tibia mountains, already described; to the west is another locality for tourmalines at Vista, and northward are, first, the Oak Grove location, and farther on those near Coahuila.
Several mines have been opened on the Mesa Grande, the Himalaya Mining Company occupying the west side of the ridge, and the San diego Tourmaline Company the east side. The latter is working a property opened by Mr. Gail Lews, at the time of the first discoveries on this mountain; he had but small success with it at first, but persevered, and reached a line pocket of gem material just before his option expired. The mine has been developed more elaborately than any other, and carried much deeper. Fine gem tourmaline are taken out from a depth of 200 feet – the greatest depth at which these gems are obtained anywhere in the world
Himalaya Mine – This mine, owned by the Himalaya Mining Company, of New York, is situated in the E ½ of Sec. 17, T. 11 S., R 2 E., SBM at an altitude of 3800 feet. The property about 4 ½ miles northwest of Mesa Grande store, and on the watershed between San Luis Rey River and Mesa Grande Creek. For many years it has been known that beautiful colored stones existed on this ridge, but after repeated failures and with no determination of quality and value, the people of the locality gave up the property as worthless. At length an agent of Mr. Tannenbaum, Heighway by name, found the locality and recognized the stones as tourmalines. This led to developments by the Himalaya Mining Company, and the present output is the result.
During 1904 about six tons of rough tourmaline were shipped to the company's lapidary in New York; of this amount, 300 or 400 pounds were fine nodules and pencils of the very highest grade.
Surface or bench digging has been followed exclusively, although a tunnel is being run to tap the ledges at the 150-foot level. Both hanging and foot walls are of hard blue diorite, and the ledge is of fine crystallized pegmatite not over 18 inches in width, and dipping at from 26 to 33 degrees southwest.
In working this ledge, pay material has been in sight continuously, and at no time has a barren piece of ground been encountered.
The upper pegmatite is usually stained with lithia and manganese and large masses of lepidolite are associated with tourmalines. The pockets are large and filled with talc and hydrous micas, in which the gem crystals occur embedded, many showing peculiar etchings. The ledge has been uncovered for about 700 feet, and to an average depth of 15 feet. These open cuts, however, are proving dangerous and will have to be abandoned as soon as the rainy season has soaked the walls on either side.
Among the minerals noted were orthoclase, albite, lepidolite, amblygonite, small clear pieces of spodumene, muscovite, tourmaline (black, green, blue, deep red, and rose), pink and aquamarine beryl, hornblende and epidotic rocks, spessartite and essonite garnet, large and very transparent quartz crystals, talc and hydrous micas, and a dark brownish transparent crystal, very dense (specific gravity, 10), and a hardness of 5½, which has not yet been determined. This mineral is very rare, and only a few pieces have been found.
Wood, water, and all natural advantages are of the best; and a good dwelling-house, barn, tool-houses, and blacksmith shop, as well as a windmill with water piped to all, constitute the improvements.
From four to ten men are constantly employed about the mine. The gross receipts for 1904 are estimated at $30,000.
San Diego Tourmaline Mining Company – The mines are situated n the E. ½ of Sec. 17, T. 11 S., R. l E., S.B.M., and about 4 miles north-west of the Mesa Grande post office. Considerable work has been done n this property since 1901, perhaps more development work than on any other gem mine in southern California. In the first place, a tunnel 20 feet long was run, tapping the ledge at 64 feet. From this, drifts were run about 150 feet in either direction, and the ledge matter was stoped to the surface. Tourmalines in paying quantities were extracted, and from this output the San Diego Tourmaline Mining Company was organized. Later a tunnel was run 286 feet in length, tapping the ledges at from 145 to 170 feet, and drifts on two ledges which were struck from 20 to 30 feet. The ledge matter is a fine-grained pegmatite, showing on both top and bottom black tourmalines in fan-shaped crystallizations. Near the center, at intervals, pockets occur in which fine gem-tourmalines are found, but not as rich as in the adjoining claim, which is the property of the Himalaya Mining Company.
This company has employed from three to seven men continuously. They have a lapidary of their own in San Diego, where most of their product is cut.
Wood, water, and all facilities are at hand. Giant powder has been used exclusively, and has not resulted in the breaking or destroying of any crystals. The ledges are over 18 inches in width, and are generally of a character which would not be prospected, looking barren and worthless, but the locality seems to be highly mineralized and many ledges show gem crystals. Other mines are being opened in the vicinity, and probably during 1905 there will be a great development in this particular section.
Esmeralda Mine, Mesa Grande – The Esmeralda Mine, owned by J. D. Stone and H. E. Dougherty, both of Mesa Grande, Cal., is situated about 5 miles northwest of the Mesa Grande store, and 1¼ miles west of the Himalaya mine, and on the eastern slope of the Temescal Valley, in the S. E. ¼ of the S. E. ¼ of Sec. 13, T. 11 S., R. 1 E., S. B. M. The mine was discovered May 7, 1904, by Mr. Dougherty, and was acquired by location as a quartz ledge. The altitude is 3470 feet.
The course of the ledge is northeast and southwest; but where the work is being done a spur running southwest and northeast at right angles with the main ledge has produced all the gems yet found. The ledge dips to the southwest at an angle of 26 degrees and is about 10 feet in width at the point opened. The claim embraces one large ledge and numerous stringers, showing gem indications. The work at present performed consists of two open outs crossing the vein and exposing it to a depth of 7½ feet; a tunnel 60 feet below the surface workings tapped the ledge at 28 feet; but no further work has been done in the tunnel, and no gems were found in the formation at that place.
Both hanging and foot walls are composed of a coarse, crystallized hornblendic diorite of a rich grass-green color, resembling a serpentine. The ledge itself is pegmatite, and is faulted in several places by volcanic action. The pegmatite is of the coarse granitic type met with in nearly all the gem mines in the southern belt. The pockets are quite large, and contain quartz crystals, orthoclase, and albite in beautiful transparent crystallizations. Lepidolite in pieces weighing from 50 to 300 pounds also occurs in conjunction with the pocket material. Tourmaline is the only perfect gem found, and occurs in pink, bright red, azure blue, aquamarine blue, and a peculiar shade of green blue, which cuts to a stone in which one set of facets shows a sapphire blue, and another set a rich emerald green. Crystals of this character have not been noticed in any other tourmaline mine in southern California, although fine blues and greens exist in other places. With the lepidolite is a granular blue and lavender mineral which could not be determined, but apparently is a lithia compound.
In examining the ledge, 2½ feet of pegmatite were found overlying the pocket stratum. The pockets themselves were filled with soil and foreign matter, rendering it impossible to say exactly what the nature of the softer material that once filled them had been. Some pockets were hollow, containing nothing but quartz crystals, while near them were pockets absolutely filled with tourmaline pencils. The lower strata or line-rock of these ledges is also pegmatitic, although of much finer crystallization than the top. About 250 feet southwest of the tourmaline workings, the ledge is badly broken and shows only in places, in the nature of blowouts of pegmatite and quartz. In some of these blowouts golden and aquamarine beryl were found frozen in the formation. Many of these pieces were of excellent gem quality, and the owners signify their intention of doing considerable development work at these places. About $300 has been expended, producing about 20 pounds of tourmaline of gem quality. As in many other cases of prospecting and mining for gems in southern California, lack of funds has greatly hindered the proper development and exploiting of this mine.
There is neither timber nor water on the mine, but an abundance of timber can be secured within half a mile. Also, water can be piped to the property from springs on the hill above. The mine next described does not furnish either gem tourmaline or kunzite, but is worked as a beryl mine, some fine material having been obtained. It lies about half way between Pala and Mesa Grande, on Palomar Mountain, which is a spur or foothill of the Smith Mountain ridge, with which Pala Mountain is closely related, and hence it is considered here.
The Mack Mine – Located at Rincon, San Diego County, in Sec. 25, T. 10 S., R. 1 W., S. B. M. This mine was discovered in November, 1903, by Mr. J. M. Mack and an Indian named J. Calec, near the Rincon Indian Reservation, at an altitude of 1960 feet (aneroid). The mine is on the Pala belt, 9½ miles southeast of Pala; the ledge has a dip of degrees to the southwest, and is exposed on the hanging wall for about 75 feet. Work has been entirely confined to the surface, and but little gem material has been taken out, although several pounds of peculiar opaque, deep-blue beryl were extracted. These crystals are different from any yet found in San Diego County, and should be analyzed. Mr. Mack contemplates a great deal of development work, however, and during 1905 it will be possible to determine whether or not this locality will produce the emerald, as indications are very favorable.
The ledge is essentially pegmatite, with an average width of from 5 to 6 feet, with a gray granite foot wall. The hanging wall was hard to determine, as a great deal of matter from the ledge had fallen down and covered it at nearly every place, but was apparently a blue and gray diorite. The pockets are very narrow and are confined exclusively to a bony crystallization of orthoclase, and most of the beryls found were frozen into this crystallization. Wherever a pocket was found in which clays or other soft substances were the matrix, the crystals were exceptionally fine and could be cut into perfect gems.
So little work has been done that it is hardly of importance to report locality if it were not for the peculiarity of the crystals found. The owners would not give the valuation of their specimens or cut stones sold, hence the product can not be estimated. There is a small spring of water on the property, and some sycamore and oak timber. The exact locality is 1½ miles north of the Rincon store, in the first canon east of said store.
Since the preceding data were collected, fine gem beryls have been obtained at this mine, which are referred to in the body of this Bulletin.
South of all these localities, lies a separate group of occurrences of garnet, with beryl and in some cases topaz, centering around Ramona, and also the garnet country far to the southeastward in the vicinity of Jacumba. These suggest a parallel line or belt of garnet and beryl, southwest of the tourmaline-kunzite line and parallel to it; but it is not possible yet to say how far this idea may be correct. The facts, as thus far known, are as follows: The garnets belong to the variety essonite, mainly, although many of them are called spessartite (manganese garnet) ; but the writer is not satisfied that this latter species really occurs. Both varieties are often called hyacinth by jewelers, and may present, as at many of these points, rich orange and fulvous shades between red and yellow.
ABC Mine — The ABC mine, owned by Mr. Henry Daggett, of San Diego, and Mr. Alex. McIntosh, of Ramona, was discovered November 1, 1903, and is situated in the S. W. ¼ of the N. W ¼ of Sec. 8, T. 13 S., R. 1 E., S.B.M., and at an altitude of 1950 feet. The property was acquired by location by the above-named parties on government land. It is about 4 miles northeast of Ramona, San Diego County, which is the nearest base of supplies. The vein has an average width of 7 feet, and runs north 35 degrees west, with a dip of 12 degrees to the southwest. The claim embraces two ledges, very promising in character.
Three places have been opened on the ledge at the eastern extremity of the claim, and at intervals of about 50 feet. The first two are in the nature of open cuts, in which the ordinary scalping process was employed, and gems taken from broken ledge matter and soil. The principal working, however, consists of a tunnel 18 feet long, from which a stope following the pay shoot for 45 feet has been run. The work is very crude, and no system seems to have been employed in the mining.
Both foot and hanging walls are of a gray decomposed diorite, in which the feldspar has been much altered, and some quartz and biotite were found. The ledge is essentially 3 feet of coarse, poorly crystallized pegmatite, stained in some places with iron and manganese. Many black tourmaline crystals with terminals pointing directly toward the pockets were observed, somewhat altered to quartz and muscovite. Below the pegmatite is a stratum varying in width from 1 to 6 inches, composed of a grayish or whitish decomposed orthoclase, with disseminated crystals of muscovite having a pinkish and lavender tinge on the outer edges. It is in this stratum, coated with albite and clay, that the pink beryls are found, generally solitary in a pocket, with two or three large blackish-green tourmaline crystals. Quartz crystals were observed both on the top and bottom of this stratum, but not in the pockets with the beryls. It was also noticed that the pink-tinged muscovite was not in contact with the beryl crystals. Contrary to what is usual in ledges of this character, the edges of the pockets do not touch between the upper and lower strata, but continue through the entire working without interruption, although widening and narrowing in places. No other minerals were found existing in the same pocket (or rounded mass of clay and decomposed spar).
Underlying this beryl-bearing stratum is about 18 inches of a soft , albite, angular in crystallization, and with numerous holes penetrating the mass. In these cavities minute essonite garnets were seen, also spessartite (?) and hundreds of serrated black tourmalines, penetrating in every direction. No gems, however, were found among these.
This stratum of albite lies frozen to the line-rock, or micaless granite, constituting the base of the ledge. The line-rock is coarse, and show less interlineations than at any other mine so far observed in this locality. In places, large portions of graphic granite occur, embedded in the upper strata of ordinary pegmatite. In this graphic granite small cavities were noticed, containing steatite and montmorillonite with lithia mica occurring at intervals. Very minute whitish crystals were found in these talcs, which appeared to be topaz, although too small for identification. In some places, also, where quartz crystals were found, disseminated crystals of pink muscovite occur, embedded and penetrating. The minerals noted were pink beryl; green, dark green, and black tourmaline crystals; essonite and the so-called spessartite, sparingly, lepidolite, muscovite, and biotite micas, albite and orthoclase feldspars, montniorillonite, steatite, kaolin, and stains of manganese and iron. Giant powder was used exclusively. Altogether about $500 has been expended, producing several pounds of pink beryl, the exact amount not being available at present. Some of these stones have been cut by local lapidaries, and show a rose-petal pink. They possess considerable brilliancy, and are remarkably free from hairs, flaws, or bubbles. One cut stone, weighing 30 carats, and without a flaw, was obtained from this mine.
Little Three Mine — This mine is owned by Mr. Dan McIntosh, of Ramona, Mr. H. W. Robb, of Escondido, and Mr. Chas. F. Schnack. This prospect was discovered in May, 1903, by Mr. Robb, who had secured a permit to prospect on land owned by Messrs. Mclntosh and Ferguson. It is situated in the N. E.¼ of S. E. ¼ of Sec. 8, T. 13 S., R. 2 E., S. B. M., and is about 4½ miles northeast of Ramona, which is the nearest source of supplies.
The vein runs northeast and southwest, at an angle of north 35 degrees west, and dips to the south at an angle of 20 degrees. The average width of the vein is 4½ feet; the altitude is 1940 feet. The work so far consists of open cuts; the vein being naturally exposed for about 60 feet on the hanging wall, it has been possible to commence work where the vein enters the ground, and break open the ledge of the pegmatite to where the pockets occur in the center. About 60 square yards of the vein have been uncovered in this manner, showing some very interesting conditions of formation. At the southeast extremity of the workings, “spessartite” garnet was encountered, associated with small green beryls in pockets of decomposed albite, orthoclase, and muscovite mica. In this portion of the ledge no tourmalines of any color, nor any topaz, were found in the pockets; but black tourmalines occurred very thickly interspersed in the upper or pegmatite portion of the ledge at this place. Also, the “line-rock,” or micaless granite, forming the base of the ledge has parallel, wave-like bands of minute black tourmaline. The associated minerals at this part were only beryl and quartz crystals, and the beryl very sparing. A concentric band of hematite and ferruginous quartz seems to separate this particular pocket from the other pocket material found in the ledge.
From this pocket, working northwest, a gradual change was encountered and a barren condition for about 10 feet. Then coarse, bone-like concretions of albite were first discovered, with large and perfect quartz crystals. The interior of the pockets lying with these minerals has either been decomposed completely and washed away, or else the pockets were hollow, without any matter filling them, as they are at present filled with the soil, which seems to be the same as that found on the hillside above the ledge. In this loose soil, and " frozen " to the albite and orthoclase, are numerous wedge-shaped crystals of topaz, some of which weigh over a pound; they are white, sea-green, sky-blue, and light yellow in color. Attached to the roof and floor of these cavities, and with a long root extending up into the quartz and pegmatite, are gigantic tourmaline crystals, deep green, mostly opaque, some of them 5 inches in diameter, and weighing as high as 15 pounds. Some small pencil tourmalines of a deep-green color and gem quality are found loose in the pockets, also a number of small topaz crystals that have become detached from their matrix of albite. Purple and pinkish muscovite in very large crystallizations and frozen into nuggets are also observed loose in the pockets, or attached to the albite. In most cases these crystals of mica are attached to each other at right angles, leaving angular holes, in which very perfect topaz crystals have formed. The output of this work has been approximately 30 pounds of topaz, 50 pounds of all classes of tourmalines, and a small quantity of “spessartite” garnet. Beryl pseudomorphs after topaz were also noticed, badly checked, but of pinkish and light yellow colors. Also quartz pseudomorphs taking the crystallization of the topaz, and in cubes and rhombic prisms, are found loose in the pockets of topaz. The ledge proper is a fine-grained granitic pegmatite, with foot and hanging walls of gray decomposed diorite. The underlying line-rock in the topaz locality assumes a banded appearance, very straight in its interlineations; it is coarser than is generally seen in ledges of this kind, and is notable for the absence of either garnet or tourmaline in any quantity, the lines or bands apparently being a stain from manganese. A little biotite was also seen. This is a very strong ledge, and can be traced without a break for over 3000 feet, with an average width of 4 feet, and in some places much wider.
No work has been performed other than that described, but the ledge shows indications of garnet for its entire length. This mine is a westerly extension of the Surprise mine, owned by J. E. Farley, James W. Booth, and Mrs G. M. Stone. There is quite a quantity of fine oak and sycamore timber in close proximity to the mines, and a spring of water sufficient for domestic uses, but which can probably be developed for all purposes needed in mining for gems.
Giant powder has been used exclusively, and no bad results have been reported. Pocket material has been extracted, and the gems taken out by the screening process only, and quite a quantity of small crystals of good quality were found in the tailings.
Surprise Mine — The Surprise mine, adjoining the last, is owned by J. E. Farley. J. W. Booth, and Mrs. G. M. Stone, all of Ramona, Cal., and is situated in the N. W. ¼ of S. W. ¼ of Sec. 9, T. 13 S., R. 2 E., S.B.M. It was discovered on patented land owned by Mrs. Stone, November 1, 1903, by Mrs. Booth, who noticed a few “spessartite” garnets sticking in the pegmatite. The three persons above-named became working partners to develop the property. The vein runs nearly due east and west, but with a slight trend to the northwest and southeast. It dips to the south at an angle of about 20 degrees, and has an average width of 3½ feet. Two places have been opened on the ledge, at intervals of about 300 feet, each showing an entirely different condition in the formations. The first is about 250 feet north of Mr. Booth's residence, which is the stage station between Foster and Julian, San Diego County. At this place the pegmatite is
finely crystallized, about 18 inches in width, and lies under a hanging wall of micaceous diorite. The pegmatite contains considerable graphic granite, with greenish stains, crystallized quartz, clear and white, and muscovite of a rich grass-green. Beneath this is an average thickness of a foot and a half of decomposed albite and orthoclase and infiltrated sand and earth, with some hydrated muscovite, and black tourmalines many of which are altered to muscovite and quartz. Disseminated through this friable mass are "spessartite" garnets, in colors from deep red to light honey-yellow, affording beautiful gems, some of which have been cut, weighing from 3 to 6 carats. About five pounds of these were taken out of a cut running along the ledge about 6 feet in depth and 18 feet long, and sin average width of 4 feet. Beneath this is the usual “line-rock,” or micaless granite, in which no garnets were noticed, but banded lines, 2 to 3 inches apart, of minute black tourmalines were seen; this would indicate that a higher crystallization of the ledge forces the lower into the wall or outer rock, as garnets are always found to occur in the lower rock of tourmaline ledges, while the tourmaline is found as embedded crystals in the lower rock of garnet-bearing ledges, in this locality. Some quartz crystals, which appear to have been etched by either fluorides or some other chemical compound, occur broken and disseminated with the garnet
The second working lies east of the first; and is more compact, with gray micaceous diorite as foot and hanging walls. This pegmatite is very finely crystallized, and is stained with iron and manganese, and has serrated black tourmalines. In the center of this ledge, lying inbetween the gray base rock and the upper pegmatite, is 6 or 8 inches of orthoclase somewhat altered. In this orthoclase occur small pockets 2 to 3 inches in diameter, filled with fine granular ferruginous quartz. In this sand, topaz is found, usually coated with a talcose clay. Those near the surface were mostly white or colorless, while at a depth of 6feet the color had changed to sky-blue and aquamarine-blue. About four pounds of these crystals have been extracted from a cut 20 feet long and extending 8 feet in depth of the incline of the ledge.
Several very fine pink beryls were also taken out, one 6 inches long, having three perfect sides, and 1½ inches in diameter, being the largest crystal yet found. About two pounds of pink beryl has been the output so far. The above amounts of spessartite, topaz, and beryl have been extracted at an expense of $250. Giant powder is used exclusively. No work is in progress at present, but further development is contemplated.
This mine is an extension of the Little Three mine, owned by Mr. Dan McIntosh et al., adjoining it on the northwest. These parties own several other ledges in the same vicinity, traversing four quarter-sections land owned by them, and lying in a line extending east from the present workings.
Timber and water are available in sufficient quantities for mining purposes. The stones are extracted in both localities by screening and washing, and the owners seem to be thorough in their work. The occurrence of a yellowish, reniform, compact and extremely heavy substance was noted in some of the topaz pockets. The specific gravity of this mineral and its peculiar color have attracted the attention of several people, but it was impossible, with the means at hand, determine what it was. From the edge of the pockets containing these nuggets, radiated black tourmalines were found, altered to a micaceous substance of sea and emerald green color, with occasional tinges of purple and rose-pink. This alteration seems to be an allied mineral to the above. Some triplite and magnetic iron occur at the junction of the foot wall and pegmatite.
The list of minerals noticed in these mines was: white and blue topaz; pink, green, and white beryl; black, green and brown tourmaline; spessartite (so called), biotite, magnetite, orthoclase, albite, quartz fine crystallizations, and the two unknown minerals above referred to.
Hercules Mine — This mine, owned by Messrs. Samuel G. Ingle and Harry Titus, of San Diego, and Mr. Pray, of Escondido, lies about 4½ miles northeast of Ramona, and about three fourths of a mile northwest of the stage station between Foster and Julian. The mine was located in August, 1903, by the above-named parties.
The work has been confined entirely to open cuts or scalping, and the gems have been extracted in all cases either from the débris or from broken pockets in the ledge, which is a coarse pegmatite, decomposed and with very little perfection, in the albite or orthoclase; but where black tourmalines penetrate this crystallization, joining on to the black tourmaline, embedded in either albite or orthoclase, are essonite garnet and so-called spessartite. The latter is of the finest quality, and has produced gems from one to six and eight carats in weight, without flaw, which are retailing at $20 a carat.
Both hanging and foot walls are a gray diorite, in which some mica can be found. The course of the vein is north 60 degrees west, with a dip of 45 degrees. The location is in the S. E. ¼ of S. E. ¼ of Sec. 6, T. 13 S., R. 2 E., S.B.M.
The method of handling the product has been confined exclusively to screening, and a good many gems have been thrown over on account of the peculiar condition of the clays which cover them; but the output so far has been 15 pounds of garnet and a half pound of very clear green beryl, which is an associated mineral with it. A few green and blue tourmalines, but not fit for gem purposes, have been found higher up on the ledge.
There is a spring on this property, which will furnish enough water for domestic and mining purposes; also sycamore and oak timber in sufficient quantity for mining.
Lookout Mine — This mine, owned by Messrs. Samuel G. Ingle and Harry Titus, of San Diego, and Mr. Pray, of Escondido, was located in the month of July, 1903. It is situated 4½ miles northeast of Ramona, and joins the Hercules mine on the northeast. The vein has a dip of 20 degrees to the southwest, and an average width of 4½ feet. The claim runs north 55 degrees west, and is located in the S. W. ¼ of Sec. 5, T. 13 S., R. 2E., S.B.M.
Work on this claim has been confined entirely to open cuts and scalping. Garnet, called spessartite, is the only gem found, although indications of beryl and tourmaline, with two or three peculiar metallic substances which could not he determined, were noticed. Both walls are of gray diorite, containing some biotite mica, although a seam of red clay lies between either wall and the ledge itself. The ledge is composed partly of feldspar, with very little quartz. In the pockets, albite and orthoclase are the mother of crystallization, and a very peculiar condition of the quartz is evident. The crystals seem to have been broken at some time into splinters, and then welded together, forming a conglomerated mass of quartz with no distinct crystallization. Adhering to this quartz, and also to the surface of the albite. are perfectly formed garnet crystals, which, in many cases, have afforded beautiful gems.
Not enough work has been done to make a satisfactory examination. About three pounds of garnet, and perhaps four ounces of fine beryl, was the total product of this mine. Some sycamore and oak timber are available; and water owned by the same parties on the Hercules mine can be used in connection with this one.
McFall Mine — This mine is situated 7½ miles southwest of Ramona, on the eastern line of the San Vicente grant. It is owned by John McFall, who located the property about ten years ago as a zinc mine, and erroneous reports were given of its value as a zinc property. On examination, no zinc was found nor any indications of it, but a large body of essonite garnet and finely crystallized epidote was shown. A shaft 22 feet in depth still remains in solid garnet, with very little impurity of quartz. Very few gems were found, however, although many handsome crystals, more or less transparent, were among those taken out. There is a certain condition in these crystals which does not produce good refraction of light, and hence as gems they have no value. The epidote, however, is the finest yet seen in San Diego County, and will probably produce gems.
Mr. McFall expects to work the property for abrasive purposes, as transportation can be secured cheap enough to make this course profitable. There are both wood and water adjacent to the property, but not on it. No work has been done on the mine for some little time. The formations are both blue and gray diorite, and the masses of garnet appear to be pockets rather than ledges.
Prospect Mine — This mine, owned by Messrs. H. A. Warnock and John P. Sutherland, of Ramona, was located on September 15, 1904, by the above-named parties, and is about 4 miles northwest of Ramona, crossing the road between Ramona and Mesa Grande, an open cut having been made on the east side of the road in Hatfield Canon.
Spessartite (so called) has been the only product in gems, although greenish tourmalines have also been found. The ledge is about 6 feet in width, of a poorly crystallized pegmatite, and most of the gems are found frozen into the ledge, few pockets having been discovered. The parties are actively at work, and probably will find a better condition in 15 or 20 feet from the present working. The output has been very small, and no sales have been made. The prospect is worth mentioning, however, as it is the last mine on the northwest end of the Ramona belt of crystallization, the belt apparently being barren for 14 miles northward of Mesa Grande. Messrs. Warnock and Sutherland expect to continue their work until something definite is known about the property, and a report two or three months later will be more satisfactory than can be had at present. There are both wood and water in plenty on the property. It is now owned by Mr. Warnock.
Dos Cabezas Mine — This mine is 17 miles north and east from Jacumba Hot Springs by road, although in a direct line only about 8 miles; it is situated in Sec. 2, T. 17 S., R. 8 E. Here many fine hyacinth garnets have been taken out from a matrix of carbonate of lime, which occurs in quantities sufficient to be used as building marble, etc. There are also indications of phosphate of lime. This locality has been worked off and on for the last ten years for gem crystals, and several hundred dollars' worth have been extracted by different parties, but nothing definite has been done, owing to its inaccessibility and the lack of wood and water. Properties now owned in that vicinity are those of Mr. James Jasper, the San Diego Desert Marble Company, the San Diego Gem Company, W. H. Trenchard, T. H. Steinmeyer, and William Hill. Development is expected during the next year.
Nine and a half miles east of Jacumba, and near Mountain Springs, on the road leading from San Diego to Imperial, and on unsurveyed land, is a locality on which three or four prospects have been located showing excellent essonite and so-called spessartite garnet. These localities are now controlled by the San Diego Gem Company, 1529 D street, San Diego, who have sunk a shaft and have done considerable surface work. The gems extracted are of exceptional quality and size. Several thousand dollars will be expended by the owners during the next year. The water supply is about 4½ miles away, and there is no timber whatever or even wood for ordinary purposes. The country is very rough and inaccessible, but bids fair to be one of the best producers of gems yet discovered in California.
Crystal Gem Mine — This is owned by Collier & Smith, of San Diego, and is situated about 8½ miles northwest from Jacumba. Pink and green beryls associated with essonite and (so-called) spessartite garnet have been the only output, but general indications arc very favorable. The ledge is a coarse pegmatite, about 8 feet in width, and extends for nearly a mile. Quartz crystals, albite, orthoclase, and indications of lithia are also found in conjunction. This property is not worked at present, but probably will be during the next year. Ten pounds of fine essonite garnet and perhaps three or four pounds of beryl were taken out during 1904. There is a spring of water on the property, and plenty of timber.
Manganese Deposits — These are owned by the San Diego Desert Marble Company, and lie 1½ miles northwest of Jacumba Hot Springs. A ledge averaging 10 feet in width and extending about 5000 feet has been located by these parties, and shows oxides of manganese associated with garnet, beryl, and black tourmaline. No development work has been done, but upon the advent of a railroad this property may become valuable, as the manganese is of exceptional quality and can be utilized in many ways.
Farther to the north and east are other localities, in the vicinity of Seventeen Palms, in the Santa Rosa Mountains, on the edge of the desert, and in the direction of Salton Lake, where Mr. H. C. Gordon reports fine and abundant occurrences of garnet. Much of this is the wild and barren region claimed by the old Indian chief known as "Fig-tree John" elsewhere mentioned.
Kunz, George Frederick
Gems, Jewelers' Materials, and Ornamental Stones of California
Bulletin No. 37 California State Mining Bureau San Francisco, June, 1905
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