Augustus Choate Hamlin
Augustus Choate Hamlin was born in Columbia, Maine in 1829. His father, Elijah L. Hamlin, was the co-discoverer, with Ezekial Holmes, of the world renowned elbaite deposit at Mount Mica in Paris, Oxford County, Maine.
Graduating Bowdoin College in 1851, A. C. Hamlin attended medical school at Harvard University. After graduating in 1854, he started his medical practice to Bangor, Maine. He authored several works on medicine, covering such diverse topics as tranmission of disease (focusing on tuberculosis) , transfusion, tetanus and “alimentation”
Hamlin served with distinction as a military surgeon during the American Civil War. He was Medical Director of the 11th Corps of the Army of the Potomac, then was promoted to the post of Medical Inspector of the regular army. He was present at the Siege of Fort Wagner (dramatized in the movie “Glory”) at the Battle of Chancellorsville. He published a book on the subject of Chancellorsville in 1896. In addition, he served as Mayor of Bangor, Maine from 1877 to 1878, and also served on the staff of Governor Frederick Robie as Surgeon-General of Maine.
Notwithstanding his other achievements, Hamlin is today best remembered for his publications of gemstones… ranging from his book entitled “Leisure Hours Among The Gems” (published in 1884) to his superbly appointed monograph on Tourmaline (1873), llustrated by color plates of crystals recoverd at Mount Mica. His also published a work on the history of mining operations at Mount Mica in 1895, also containing color plates of Mt Mica elbaite.
In 1890, W E Hidden and S L Penfield described what they believed to be a new phosphate species from Stoneham, Maine and named in
Hamlinite in A C Hamlin’s honor. It was subsequently determined that the new species was, in fact, goyazite, and was discredited.
Hamlin amassed an amazing collection of Maine tourmaline crystals, which he sold to James Albert Garland, a prominent New York City collector of gemstones. Garland in turned donated the collection, as well as his own collection of gems, to Harvard in 1892.
Hamlin died in 1905.
The following excerpt is taken from his book “Tourmaline” published in Boston in 1873 by James R Osgood & Co. [Please note that Hamlin used many idiosyncratic spellings common in the 19th Century... "bowlder" for "boulder", "felspar" for "feldspar" and (very oddly) "karat" for "carat".]:
DESCRIPTION OF MT. MICA AND ITS MINERAL TREASURES
by Augustus Choate Hamlin
THE most remarkable locality of the tourmaline in the United States, and which is also one of the most celebrated in the world, is in the town of Paris, in the State of Maine. It occurs on the brow of a little hill, which has been named by the mineralogists Mt. Mica, from the abundance of the muscovite which occurs there. The hill is one of the spurs of a more considerable elevation called Streaked Mountain, from the rugged and denuded appearance of its sides. It is but few rods square in extent, and is covered with turf and alluvial earth, with the exception of a little space in the centre and at the summit, where the ledge bursts out to the view. Although it appears coarse and utterly valueless to the casual glance, it is, nevertheless, one of the most remarkable mineral deposits on the face of the globe; for it has yielded from an area thirty feet square nearly forty varieties of minerals, some of them of extreme beauty and rarity.
It was discovered in the year 1820 by two students by the name of Elijah L. Hamlin and Ezekiel Holmes. They had been searching for minerals during the day along the mountain ridge to the southward, and were then descending the western declivity on their way to the village. It was on the last day of autumn; and the glimmering rays of the setting sun were gilding with renewed splendor the faded colors of the landscape as the students were passing over the top of one of the lowest knolls. The view of the distant mountains (which are the loftiest in New England), the intervening valleys softened with purple shadows, the patches of green grass in the meadows untouched by early frost, the variegated hues of the forest leaves left by the autumnal winds, the broad extents of russet brown of the stubble fields, contrasting vividly with the glorious hues of the sunset sky, composed a scene of exquisite loveliness. The youths, spell bound by the entrancing beauty of the landscape, lingered upon the hill top until the valleys were shrouded with the shadows of commencing twilight. As they turned to descend the hillock, a vivid gleam of green flashed from an object on the roots of a tree upturned by the wind, and caught the eye of young Hamlin. Advancing to the spot, he perceived a fragment of a transparent green crystal lying loose upon some earth which still clung to the root of the fallen tree. The student clutched the gem with eagerness; and calling back his companion, who had passed over the brow of the hill, they closely searched the surrounding soil for other specimens. But the rapidly increasing twilight soon compelled the youthful mineralogists to abandon the search. They, however, resolved to return at daybreak, and continue the exploration. But during the night a storm arose, and covered the hill and its adjacent fields with a thick mantle of snow, which remained until spring.
As soon as the whiter snows had melted away, and left the hill and its sides exposed, the students returned to the search. They went directly to the ledge, which crops out on the summit of the hill, and which they had not examined before darkness overtook them on their previous visit. As they climbed up over the smooth and denuded surface of the rock, they were astonished to observe many crystals, and fragments of crystals, lying exposed upon the bare ledge, and sparkling in the rays of the sun. These they carefully gathered; and tracing others to the earth below the ledge, and which had formed from the decomposition of the rock, they eagerly turned up the soil in search of its hidden treasures. Thirty or more crystals of remarkable transparency and beauty rewarded the labors of the students; and with joy they held them up to the sunlight, and admired their varied colors of green, red, white, and yellow, of different shades. They had, indeed, stumbled upon one of the richest and rarest of Nature's laboratories. All around the brow of the ledge, enormous masses of rose red lepidolite, splendid groups of crystallized quartz of white and smoky hues, crystals of tin, broad foliae of glistening mica, snowy flakes of felspar, studded with transparent green and red tourmalines, lay scattered about in profusion. Collecting as many of the choice and beautiful specimens as they could carry, the students, heavily laden, returned to the village, and sought to ascertain the nature of their mineral treasures. Subsequent examination indicated that the ledge was perforated with cavities, in which the tourmalines and other rare minerals had been deposited. It was also evident that the crystals that had been gathered up by the students had been set free from their cavities by the decomposition of indefinite periods of time, which had removed the surface of the ledge. There was no evidence of drift; and the crystals lay exposed upon the rock; while the softer materials had been washed by the rain down to the base of the ledge, and accumulated as soil. Parts of the ledge yet exposed to view were fairly honeycombed with small cavities and soft spots, where the decomposing felspar was crumbling away. In these cavities and decayed places in the rock other tourmalines were obtained by breaking away the edges of the ledge, or removing the decomposed stone.
The discovery having been made known to the villagers, many of them hastened to the spot, and secured a number of fine specimens as trophies or mementoes. As no one in the vicinity was able to distinguish the character of the gems, or even make known their name, the students enclosed a few of the smaller crystals in a letter to Prof. Silliman, and requested him to describe them. He kindly and promptly informed the youths that the minerals were tourmalines, and of rare occurrence. Thereupon the students selected some of the finest and purest of the crystals, and addressed them to the professor in return for his kindness. The parcel was intrusted for safe keeping to the late Gov. Lincoln, who was then a member of Congress, and about to start for Washington. At this period the journey to the capital was a serious undertaking; and the condition of the roads required that it should be made on horseback, at least for a great part of the distance. The governor started safely with the precious package, but lost it before reaching New Haven; and no trace of it has ever been found.
Mt. Mica Elbaite Crystal
The younger brother and survivor, Hannibal, took but little interest in mineralogy, and gave his share to his brother. He now remembers only the facts of the discovery, the curious and symmetrical forms, the perfect limpidity, and the wonderful beauty, of the crystals. This is all that is known of the history of the splendid gems and wonderful crystals that Mt. Mica yielded to the explorer in its early and best days. Gathered then in profusion, and carelessly treasured, they have since been scattered over the world, and, in many instances, their identity lost. The late Prof. Cleaveland, a famous mineralogist in his day, received several fine crystals, and among them a superb yellow tourmaline of the purest water. There is now no trace left of these specimens. His cabinet, which Bowdoin College inherited, does not now contain them; but, from the evidence gleaned from his correspondence, it is surmised that they may have been sent to his friend, the celebrated Berzelius, and are now in the mineralogical cabinets of Sweden. Those that fell to the share of young Holmes at the time of the discovery were destroyed many years ago in the fire that burnt the Gardiner Lyceum. In the Imperial Collection of Minerals at Vienna, there are some tourmalines of remarkable beauty; and mineralogists are at once struck with their perfect resemblance to the Maine tourmalines, especially in their arrangement of color. They came from the cabinet of the antiquary Vander Null, and were simply labelled "America." This is all that is definitely known of them. As the tourmalines of all known localities have peculiarities which distinguish them in a marked degree from each other when viewed by the practised eye, it is easy for the mineralogist to give the locality to the unlettered specimen. Moreover, from the evidence now in our possession, we feel confident that these tourmalines at Vienna are a part of the results of the early exploration of Mt. Mica. Baron Loederer, an experienced mineralogist, happened to be in Vienna when the Austrian government purchased the collection of Vander Null. He was present at the museum when the boxes were opened; and as he had visited Mt. Mica previously, and was familiar with the peculiarities of the mineral, he at once recognized them to be identical with the tourmalines of Maine. He believed them to have been taken from Mt. Mica previous to the year 1825. The baron is now dead; but this information was communicated to a geologist in this country prior to 1830. In the Vienna cabinet there is one crystal of tourmaline with both terminations complete. Among those found by the Hamlin boys was a crystal that coincides with this description; and tourmalines of this perfection are of extraordinary rarity.
In 1825, five years after the discovery, Prof. Shepard, a young and enthusiastic mineralogist, visited the locality, and observed a decayed place in the ledge, where a mass of felspar had become decomposed. By digging out this substance, and removing the superincumbent earth, a drusy cavity, or series of cavities, three feet in length and two in depth, were exposed to the gaze of the fortunate explorer. At the bottom of these cavities, among particles of cookeite, lepidolite, and other decomposed minerals, resembling sand, lay a number of magnificent tourmalines of perfect transparency, and exhibiting colors of red, blue, green, and also of variegated hues. Some of these splendid crystals were several inches in length, and more than an inch in diameter; but, unfortunately, they were not in perfect condition. The rain trickling down from the surface of the ledge, through its crevices, had, by the effects of freezing and thawing, cracked and shattered portions of the. crystals. The terminations of some of them were broken into fragments; while the shafts remained entire, or slightly fissured. Some of these prisms were green at one extremity, and ruby red at the other, or green on the exterior, changing imperceptibly to a beautiful crimson in the interior. Others were entirely green or red or blue, or variegated.
The fame of Mt. Mica now became known far and wide; and mineralogists from all parts of the country hastened to visit and explore the locality. The Russian and Austrian consuls, Mr. Cramer and Baron Loederer, both enthusiastic collectors, examined the deposit, and carried away large quantities of fine specimens.
All the accessible part of the ledge had now been explored; and mining operations of a more solid character were required to follow the continuation of the deposit, which still appeared at the bottom of the excavations. The ill fated Prof. Webster blasted down a few feet, and opened a cavity which yielded a grass green crystal of great purity, quite as long as the finger. At a subsequent time he discovered another cavity, from which he drew out a superb red crystal the size of the thumb. The excited and overjoyed professor sprang to the top of the ledge, and, holding up the beautiful gem in the rays of the sunlight, danced over the rock like a madman, exclaiming that he would not take a large sum of money for it. Nothing more is known concerning these remarkable specimens; but it is surmised that they were sent to Europe, and were probably cut into gems, and may now adorn some of the royal crowns.
From time to time, during a period of more than forty years, many other explorers visited the locality; but they examined it in a superficial manner; and in the year 1865 the deposit was regarded by mineralogists as completely exhausted, although the excavation in the ledge did not exceed fifteen feet square, nor more than six feet in depth. At this time the writer carefully examined the hill, and found no signs of tourmalines, with the exception of a small piece of lepidolite, which appeared in the pit at the base of its southern wall. With the aid of a miner we placed a blast in the rear of the lepidolite; and, to our joy, the explosion revealed a small cavity about the size of the fist, in which lay a crystal of green tourmaline tipped with red, and an inch in length. Encouraged by this success, we commenced a series of careful explorations, which, undertaken at various times extended over a period of three years.
Mt. Mica Elbaite Crystal
The year following this abandonment of the mine, a party of explorers, searching for mica for commercial purposes, commenced operations at the same place, and proceeded to remove the rock on the eastern side of the pit. They removed about three hundred tons of rock, and descended to the depth of quite eight feet. At nearly this depth, the miners struck five well defined cavities on a line ranging from east to west, but disconnected with each other. All these cavities contained tourmalines in broken crystals of various colors; and in one of them was deposited in and on a mass of white quartz one of the most remarkable groups of tourmalines yet discovered in any part of the world. Separated into fragments by the ignorant miners, they were scattered in various cabinets, and some even cut into gems, before the mass of quartz which served as the matrix was discovered. However, their dimensions were preserved; and from the remaining crystals and fragments the group has been reconstructed in miniature. The mass of quartz was about eight inches square, and five in depth. On its summit arose a crystal of tourmaline two inches in diameter, and fully two and a half in height. It was transparent; pink at its base; changing, towards the summit, to a delicate and gorgeous carmine of considerable depth of hue. On the side of the quartz matrix appeared a fine prism fully three inches in length, and three fourths of an inch in its longest diameter. This crystal was transparent, and of the purest grass green; in fact, some of its fragments cut gems resembling very closely the finest of the Peruvian emeralds. Another crystal, of unknown length, but more than an inch in. diameter, was of a beautiful blue green in its centre, surrounded with a coating of clear white tourmaline a line in depth. This was also surrounded by three other layers of transparent tourmaline, each about a line in depth. The first was pink in hue; the next, limpid white; the last, and the exterior, was a soft celandine green. The fragment which has been preserved, when viewed axially, presents plainly this remarkable arrangement of color. There were other crystals of white and green, or white passing to a very light blue. The whole number of distinct crystals arising from the mass of quartz as a matrix were nine; and all were transparent.
The writer, again taking courage at the success of the mica hunters, commenced explorations on the northern and eastern wall of the pit. Several fine specimens of rose red lepidolite, and some other lithia minerals, appeared on the side of the excavation to give hope to the mineralogist. Eighty tons of rock were removed in this operation before a cavity was struck. One ton of lepidolite was obtained, including a large mass weighing five hundred pounds. The cavity proved to be a large one of more than a bushel capacity, and yielded a great number of minute crystals of tourmaline, besides several large specimens, which, unfortunately, were in a state of disintegration. Some months afterwards the exploration was continued, and in the same direction, - to the northeast. After removing forty tons of rock, a small cavity the size of the hand was opened, and yielded a broken crystal of dark green the size of the thumb, and a remarkably slender prism of bluish green more than three inches in length, and one fourth of an inch in diameter. This singular specimen is a facsimile of some of the Siberian beryls, and will readily pass as such.
In this last exposure of the ledge, no lepidolite, and very few of the associate minerals that accompany the tourmalines, were obtained; and, from the appearance of the wall, the miners concluded that the eastern limit of the mineral deposit had been reached; therefore the exploration in that direction was stopped.
The next summer the western flank was examined; and, a few preliminary blasts having yielded positive signs, the miners were directed to blast out an extent of the ledge amounting to about sixty tons. During this removal, several decomposed spots in the albite, enclosing tourmalines, were discovered; and finally a large cavity was reached, which yielded many minute crystals of pure white tourmalines, and fragments of what were once magnificent crystals of white and red, and white and dark blue. A month later in the season, the work of blasting out the western flank was resumed. Fifty tons of rock were removed; but not a single tourmaline, nor a specimen of the rare minerals associated with them, was obtained. We then arrived at the conclusion that both flanks of the deposit had been reached; and the only hope of obtaining further tourmalines lay in blasting out the central portion of the ledge. To reach the imaginary line of the tourmaline deposit will necessitate the removal of large quantities of rock to the depth of eight feet; and, as this operation will require a large expenditure of labor and money, all further attempts to explore the ledge have been abandoned. We do not, however, consider the locality as totally exhausted; but we regard all future mining operations in search of the tourmalines as extremely hazardous and costly.
From the data afforded by the removal of many hundred tons of rock, and the exposure of a large extent of the mineral bearing portion of the ledge, we have arrived at the conclusion that there is no well defined deposit; neither is there any semblance to a vein in which these minerals may be traced with a degree of certainty. But there is an indefinite arrangement, an imaginary line at a fixed depth below the surface, in which we find the tourmaline deposits, and, in fact, all the other rare minerals for which Mt. Mica has become famous. This line dips to the south east, and descends gently from the place discovered by the students down to the bottom of the southeastern wall of the pit, where it disappears eight feet below the surface.
To describe this strange deposit in strictly scientific terms will indeed be a difficult task; but we will endeavor to make it appear in the same light to our readers as it appeared to us. The ledge, in its early days of examination, seemed to be foliated, but not stratified; and consisted of layers of granite, bending with gentle inclination toward the north west. This inclination of the layers, at first gentle, is now observed, at the back of the pit, to be almost perpendicular. These folds of the granite lay like the leaves of a book, but not of a definite thickness. As they bent over to a certain extent, the coarse granite of the superior rocks suddenly changed in character. It was granite still; but the arrangement of its particles had undergone a decided change. The masses, flakes, and coarse crystals of albite, the large nodules of quartz, the broad plates of mica, and the huge and numerous crystals of schorl, vanished; and, instead of them, a ledge appeared of firmer texture, but composed of much smaller particles of the same materials. The line of demarcation was quite apparent; yet there was no line of decided and distinct separation. Along this imaginary streak of changed arrangement of material occurred the tourmaline deposits. They sometimes happened in the folds of granite a foot or two above this line, but never below it. Of all the twenty cavities known to us, we are not aware of a single one occurring below this change in the rock. The early explorers found the deposits at the surface, and followed them to the southward, about fifteen feet in distance, where the streak had declined to the depth of six feet below the surface. There was no direct communication between these cavities, or pockets; but the soft and partly decomposed rock indicated deposits beneath or beyond. In fact, the fifteen feet square extent of ledge excavated in the early days was fairly honeycombed with cavities. But the later explorers were obliged to grope in the dark, and trust to hazard in their search for the mineral treasures. Cavities were suddenly found at a considerable distance from the first workings, and often when hope of success was nearly abandoned. The appearance of lepidolite was often a sign of coming success, especially when followed by masses of smoky quartz. When a broad layer of felspar was found to be changing into regular and broken flakes, a deposit or a cavity might safely be prophesied to occur beneath.
Interspersed throughout the ledge in great abundance appeared well defined but shattered crystals of black tourmaline, some of them more than a foot in length. In the rear wall of the pit, a huge crystal nearly three feet in length may be seen to day dislocated and shattered. But, strange to say, among all the cavities in which the transparent tourmalines were found, not a single crystal of the black variety occurred. It is a remarkable fact to be considered in the formation and deposition of this mineral.
The cavities generally were roofed with albite; whilst the sides were composed of limpid or smoky quartz mixed with lepidolite, crystals of tin, spodumene, amblygonite, and other rare minerals. These cavities were of irregular shapes, and of sizes extending from the capacity of a pint to that of two or more bushels. The interior was always filled with a substance resembling sand, but which is probably disintegrated cookeite and gray lepidolite. Lying loose in the sand, and generally at the bottom of the cavity, appeared the beautiful tourmalines, often unattached, and disconnected with any matrix except the loose sand. Sometimes, however, they were attached to the walls of the cavity, or, broken by unknown cause, became separated from their matrix. Occasionally the quartz rock would form fine crystals of pellucid or smoky quartz, which were often transfixed with slender crystals of tourmalines of various colors.
The walls of the cavities, though composed of the strongest materials, were often found rent and shattered by some unknown disturbing force; perhaps by electricity, but probably by the mighty effects of sudden contraction and expansion caused by the freezing of the water which trickled down through the crevices of the rock above, and exposed to the frosts of winter and the heats of summer. To these agencies do we feel inclined to ascribe the shattered condition of the crystals. Sometimes the shafts of the prisms were broken into two or three pieces; and in other instances they were fractured into numberless minute fragments. When the superincumbent sand was removed, the broken and disintegrated crystal might be seen in its bed with undisturbed outline; but, at the first touch, the symmetrical form crumbled into particles both coarse and minute. Nature had evidently constructed her forms of crystallization in absolute perfection; and the process of disintegration happened long afterwards, probably from external violence.
From the evidence collected by or known personally to us, we believe that Mt. Mica has yielded over a hundred crystals which would be considered as fine and remarkable specimens. Of the smaller tourmalines, ranging from one inch down to microscopic size, no fair estimate can be made; but they amount to many thousands. We have seen specimens containing more than fifty distinct and transparent crystals embedded in masses of lepidolite, cookeite, and albite. Coarse and opaque, or even translucent, crystals of tourmaline, several inches in diameter, and nearly a foot in length, have been found in the great masses of albite and quartz; but all the fine and transparent prisms have been taken from the cavities, with very few exceptions. These exceptions refer to a few crystals found in portions of felspar, which were soft and pliable, and of similar character to the distinct cavities.
From the data thus far obtained, it is also evident that this deposit which affords the tourmalines is of but little depth, and limited in its area. This superficial degree of deposit is not confined to the tourmaline alone, but is observed with most of the gems, and with some of the metals. It seems as though the light of heaven was required in the production of the gems, as it is for the marvellous and varied hues of the flowers of vegetation. Thus far, nearly all of our precious stones have been found on or near the surface of the earth; and it appears as though the contact of the air or a ray of sunlight was required to build up their forms and perfect their hues. Down in the thousand mines along the slope of the Rocky Mountains the amethyst vanishes below the depth of twenty or thirty feet, while the same quartz crystallizes in its beautiful and definite but colorless forms in the depths of the deepest mines. The diamond and the sapphire belong to superficial terrains; and we find that the rule of shallow deposit relates to most of the gems. The topaz of Brazil, the beryl of Siberia, the chrysoprase of Silesia, the turquoise of Thibet, or the opals of Hungary, all occur near the surface of the earth, and are never found below a certain depth.
Mt. Mica Elbaite Crystal
But in some specimens the colors are not mingled in the least, and the line of demarcation is well defined and trenchant. So sharply distinct are these crystals in color, that they seem to be composed of several sections veneered together; yet these stones are homogeneous, and cannot be cleaved apart any more than the bands of the onyx.
One very beautiful crystal exhibits a most singular appearance of alterations; and its summit, which is regularly faceted with natural planes, is changed to white to the depth of a line. The contrast of this white cap to the green column of the crystal is so perfectly marked as to suggest the idea that it may be an accidental coating; but examination proves it to be an inseparable part of the crystal.
With the tourmalines of this locality we have noticed that the faceted terminations are always green; while the red is never seen except at the termination, which is flat; that is, in well defined prisms. The crystals may appear entirely red; but they are not terminated nor well defined. This rule is not observed so markedly with the Siberian tourmalines; for with them some of the most beautifully faceted terminations are red. Sometimes the minute crystals may be found penetrating limpid quartz, like the specimens from Ekaterinsburg, which are cut into gems and ornamental stones. They then appear like arrows of rutile enclosed in quartz, but of red and green hues; and from their variety, as well as beautiful appearance, are highly prized by the Russians.
Masses of gray lepidolite and cookeite have been observed filled with crystals of tourmaline, hollow, like thin tubes of glass, with their interior coated completely or partially with yellow cookeite arranged in filaments, in tufts, or in masses. Some crystals have been found composed of a columnar structure, made up, as it were, with bundles of acicular crystals. Others hare been observed strangely compressed in their form; and sometimes, when occurring in the mica, they have been reduced to a line in thickness, even when two inches in length.
Well marked specimens of dislocated and curved crystals have frequently been found; and some beautifully radiated tourmalines of a transparent green color have been exposed by rifting masses of mica. Sometimes we observe in the solid masses of quartz or felspar well defined crystals of tourmalines articulated like pillars of basalt, and whose sections have been separated at some distance by the intervening rock. These singular modifications give rise to curious speculations as to their cause. The separation has evidently taken place while the crystal was forming; for the shaft of the prism is often complete and symmetrical, although its sections may be separated at the distance of several inches. This peculiarity is noticed with all the varieties, but is particularly marked in the black crystals: and so liable are they to this defect in homogeneity, that solid sections, or even masses, are rare; and a complete, unbroken prism has not yet been found.
What was the disturbing force? and at what period of the deposition of the mineral and its matrix did it take effect? These are themes of inquiry which are easy to conjecture but difficult to determine.
Sometimes the acicular crystals are drawn out to a delicate fineness; and, in several instances they have been seen arranged in groups and as minute and silken as the thistle's down. Massive and opaque specimens have been occasionally met with; but they are rare: for the force of crystallization has left its impress upon almost every rock at Mt. Mica, and the rigidity of its laws has been well marked at this locality. Many perforated crystals have also been seen, occurring in thin, glass like tubes sometimes more than an inch in length, but generally less. The interior of these singular crystals is often free from any substance; but some of them are filled with kaolin or cookeite of gray, white, or yellow shades.
In some of the masses of quartz, mixed with cookeite and lepidolite, remarkable but small cavities may be observed. These cavities are often empty; and their sides are beautifully striated, as though Nature had prepared a mould, and intended to deposit crystals of tourmalines therein, but had forgotten to do so. Some of these cavities are studded on their sides at random with minute transparent crystals of quartz partly covering the beautifully defined striae.
Some prisms have been observed transfixed by other crystals of tourmaline, indicating that opposite forces were at work during the process of crystallization. All the crystals have not perfect terminations; and often we meet them without any well defined faces. Some of those found embedded in kaolin are of irregular form, and indicate that Nature, restrained by disturbing causes, has left her work imperfect both in symmetry and color. This hiatus in the regularity of the deposit is far more common in the pale pink tourmalines than in any other. Some of these irregular tourmalines are translucent, and composed of columnar like masses, having the lustre and adamantine refraction peculiar to some varieties of felspar. Many of the crystals are coated in places with a thin deposition of cookeite, generally of a white, gray, or yellow hue. Some of the smaller prisms have been found completely enveloped with cookeite.
This rare mineral, cookeite, appears to be peculiar to the deposits at Mt. Mica and Hebron; for, amongst all the specimens of tourmaline we have seen from other parts of the world, not one exhibits the least trace of it. It belongs to the lithia group of minerals; and if it is really a product of alteration of the tourmaline, as some mineralogists suppose it to be, it is remarkable that it has not been found in some of the other tourmaline localities in Siberia or Brazil. Some large masses of cookeite mingled with gray lepidolite have been literally filled with transparent crystals of tourmalines of various colors, and of a great variety of shapes and conditions. Not only single prisms, but also multiple crystals and radiated forms, might be observed in these masses. Their deposition in the matrix, without any regular arrangement, recalls to mind the singular beryls of the Adun Tschilon in Siberia, and which lay at all angles in the mass of hydrous oxide of iron. Some of these remarkable cabinet specimens have been found containing fifty or more defined crystals of tourmaline.
Transparent tourmalines of similar forms and colors have also been discovered on the side of an abrupt hill in the town of Hebron, about seven miles south east of Mt. Mica. This locality was also discovered by accident. An itinerant lecturer who possessed a love for the beautiful and rare in Native, and who had passed hours at Mt. Mica studying the geological formation of the place, was travelling through the town of Hebron, on his way to the neighboring village, not many years ago. As he rode along the valley, he espied a bowlder of rose red lepidolite in the stone wall by the roadside. He recollected that this rock was one of the associate minerals of the tourmaline; and this discovery tempted him to seek for the parent ledge whence the mass had become detached. Climbing over the wall, he observed other fragments in the adjoining field; and, by tracing in this manner the surface of the ground, he soon came to the hillside, where the evidences were far more numerous, and where the deposit undoubtedly occurs. The ledge, however, is yet covered several feet deep with alluvial soil; and only the detached bowlders have been explored. These have yielded beautiful crystals of transparent and varied hues, and also the same association of minerals we observe at Mt. Mica. The surrounding earth has not been sifted, nor the ledge exposed: therefore it is not known whether the system of cavities prevails here as at Mt. Mica; but there is reason to presume it does, and that some bold explorer may one day reap a rich harvest for his labor.
Some curious specimens of altered rubellites have been found at this place. They seem to have changed into lepidolite, and still retain some of the characteristics of a natural crystal. As naturalists observe hybrids among animals, so mineralogists observe hybrids among minerals, resulting from mixture of isomorphous matters in all proportions. Sometimes one ingredient preponderates sufficiently to locate the mineral with the species to which it belongs; at other times they are all so evenly balanced, that it is difficult to determine the character of the compound: and so these rubellites may be found of all degrees of alteration, until their forms are lost, and the mineral is decidedly lepidolite.
It is a curious fact, that, by the agency of certain mysterious forces, pseudomorphs are formed; that is, crystals undergo a change of composition without their forms being in the least degree affected. Even cavities are sometimes emptied of their contents, and minerals of a totally different character deposited therein. The locality at Hebron is now known as Mt. Rubellite, deriving its name from the abundance of red tourmaline.
Five years ago, the same strolling preacher called at the house of a physician in the town of Minot; and, observing on the mantle a specimen of rock containing a green tourmaline, he inquired whence it came. The doctor pointed to a naked ledge of rock on the brow of a hill in Auburn, nearly two miles distant, and informed the inquirer that it was the locality. Not at all daunted by the distance, our venerable enthusiast started for the hill, and soon made known to the world a new locality of transparent tourmalines. The name of the discoverer of these two localities is Luther Hills.
Early informed of the discovery, we called to the place our miners from Mt. Mica, and proceeded to explore the deposit. We found that the tourmalines appeared on the brow of a ledge which projected a little distance from a gentle slope of a hill, and far below its summit. The surface of the rock and adjoining earth was strewn with numerous folise of mica containing crystals of transparent tourmalines, and large masses of pink lepidolite, amounting in all to quite a ton in weight. The abundance of lepidolite and mica gave hope of an extensive deposit of the coveted crystals; and almost the first specimen picked up from the soil, exhibiting rich emerald green hues, gave promise of superior gems. But we found, to our regret, that the deposit was very superficial, and was, in fact, a mere coating to the ledge. A few blasts of the miners soon exposed the entire deposition of the tourmalines and their associate minerals.
The tourmalines found here were of the true emerald green; and the specimen first found yielded a fine perfect gem of two karats, resembling perfectly the emeralds of Peru, but of a pale tint. Nearly all of the crystals were acicular, or in acicular groups; and some of them were beautifully radiated on plates of mica. Quite all of the specimens obtained were of emerald green colors of various intensities of shade: very few exhibited faint pink or rose red hues.
It is a little remarkable that all of these localities should occur on a direct line from each other, and invariably exposed to the west. The Auburn deposit occurs twelve miles south east from Mt. Rubellite.
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