Crown Jewel Mine, Bautista Canyon, Cahuilla District, Riverside Co., California, USA
|Latitude & Longitude (WGS84):||33° 38' 5'' North , 116° 47' 48'' West|
|Latitude & Longitude (decimal):||33.63500,-116.79694|
|Köppen climate type:||Csa : Hot-summer Mediterranean climate|
NOTE: This mine is not listed in the USGS MRDS database.
Good name in man and woman, dear my lord,
Is the immediate jewel of their souls:
Who steals my purse steals trash;…
But he that filches from me my good name
Robs me of that which not enriches him,
And makes me poor indeed.
-William Shakespeare (1564-1616). As You Like It, II, 7
The Crown Jewel mine is located in Bautista Canyon, near the junction of the Bautista Creek and Alessandro trail. The mine is accessed by Bautista Canyon road east to a forest development road which heads south to the Allesandro trail head, at which point a crude trail runs eastward up Bautista Creek to the principal mine workings at an elevation of approximately 2920 feet above sea level. (SE/4 Section 20, T6S, R2E, SBM).
The geology of the mine area is dominated by a northwest striking, southwest dipping micropluton several miles in length which consists of grey-black hornblende diorite to gabbro of the Mesozoic era. Chemically complex pegmatites follow a strike and dip relative to this rock, and are most likely genetically related to diorite injections associated with rifting and deformities caused by reduced outer temperatures of the micropluton. Other geologic units exposed within the mine area include meta sedimentary rock consisting of mica schist and fine grained gneiss of the Paleozoic era. These units appear locally as banded and folded layers, generally following the strike and dip of the gabbroic rock. Additionally, Cenozoic era gravels of the Quaternary period form an alluvial fan which has been dissected by the waters of Bautista Creek.
The deposit consists of a single complex granite pegmatite dike averaging 10 feet in thickness which follows a general northwest strike and dips between 35 and 50 degrees to the southwest. The vein-like dike is traceable along the surface for over 200 feet, and is inferred to extend for a distance of at least 800 feet in length overall. Gem-bearing pockets containing coarse crystals of quartz, feldspar and apatite have been discovered within the central part of the pegmatite as exposed along the surface. The dike is characterized as quartz-subhedral perthite pegmatite forming distinctly localized areas of dramatically enlarged crystal structure in which gem pockets are found.
The Crown Jewel mine was originally discovered by local prospector David Bernstein of Century City in March of 1990. Bernstein had chosen the area to search for crystals after research had proven the area to likely contain gem bearing pegmatites similar to those known to occur within the range immediately southward. Quite by chance, Bernstein drove up Bautista Canyon from the nearby town of Hemet, and decided to start his search near the Allessandro trail head. With the surrounding terrain being steep and brush-covered, Bernstein decided to hike up the creek which seemed less foreboding.
Making his way several hundred feet up the creek, Bernstein noticed a pegmatite hidden by thick brush where the Bautista alluvial and gabbro met. Figuring this to be the best spot to search for crystals, he began to look for cracks within the pegmatite large enough to permit the use of hand tools needed to pry apart the exposure. While working with a pick, a large gap began to develop along a bulbous portion of the pegmatite which contained large roots from a giant Manzanita growing into the crack. Bernstein decided at this point to hike back to his 4WD parked at the trail junction, and drive the truck up the creek bed to the spot where he had been working and use the winch on his truck to pry apart the rock.
With the winch cable wrapped around the troubling rock and roots, Bernstein began to successfully pull apart the exposure. Soon a large suction sound was heard as if he had uncorked a wine bottle. Going over to inspect the rock he had just removed, Bernstein was surprised to find within the dirt and roots - a seemingly endless amount of fine smoky quartz crystals, the largest measuring over a foot in length. Over the next two weeks using little more than hand tools, Bernstein continued to remove many fine crystals from the clay filled, crystal lined cavity which was becoming increasingly large in its proportions. The principal development had now grown to a cut 20 feet long, up to 5 feet wide, and nearly 6 feet deep.
While working what was becoming the back section of this large pocket, Bernstein recovered several hexagonal crystals of a blue-green color, unique from the mass of smoky quartz crystals he had been removing. The largest of these unique crystals measured over 5 inches tall and 3 inches wide. Unsure as to the exact identity of these strange crystals which were thought to be beryl of the emerald variety, Bernstein decided to seek out a person qualified to positively identify the gems and appraise their value. Finding a local gem dealer in Fallbrook, San Diego County, Bernstein learned that the crystals he had discovered were actually a calcium fluorine, hydroxyl phosphate, or simply apatite. Although gem-quality fluorapatite is very much like beryl in most physical attributes, and being considerably rare - it was not as intrinsically valuable. However, the location of this new find did add substantial value to the fluorapatite crystals, considering nothing of the size had ever been known to occur within the pegmatites of this remote mountainous region of Riverside County.
The gem dealer being rather shrewd, and very interested in obtaining these fine mineral specimens, proceeded to convince Bernstein that he could obtain many large crystals just like his best one for next to nothing from other localities around the world, and offered to trade some small gem tourmalines from San Diego County for the best of these fluorapatite and quartz crystals from Riverside County. Unwittingly, Bernstein agreed to the trade and walked away with only a margin of what he later would learn was a substantially valuable mineral discovery.
On April 4th, 1990, Bernstein officially located a lode mining claim on the deposit, naming it the Crown Jewel Mine (CAMC 235305). Minor work continued intermittently until 1994, and several small pockets containing smoky quartz crystals were found. Ultimately, another large pocket similar to the first proved elusive as the rock at depth became exceedingly hard and difficult to remove using hand tools - and thus the deposit was eventually abandoned.
6 valid minerals.
This geological map and associated information on rock units at or nearby to the coordinates given for this locality is based on relatively small scale geological maps provided by various national Geological Surveys. This does not necessarily represent the complete geology at this locality but it gives a background for the region in which it is found.
Click on geological units on the map for more information. Click here to view full-screen map on Macrostrat.org
|Late Cretaceous - Paleoproterozoic|
66 - 2500 Ma
|pre-Cenozoic granitic and metamorphic rocks undivided|
Age: to Cretaceous (66 - 2500 Ma)
Stratigraphic Name: Ash Mountain Complex; Placerita Formation; Sur Series
Comments: Southern California, Mojave Desert, Sierra Nevada, central California Coast Ranges
Reference: Horton, J.D., C.A. San Juan, and D.B. Stoeser. The State Geologic Map Compilation (SGMC) geodatabase of the conterminous United States. doi: 10.3133/ds1052. U.S. Geological Survey Data Series 1052. 
66 - 145 Ma
|Mesozoic intrusive rocks|
Age: Cretaceous (66 - 145 Ma)
Lithology: Intrusive igneous rocks
Reference: Chorlton, L.B. Generalized geology of the world: bedrock domains and major faults in GIS format: a small-scale world geology map with an extended geological attribute database. doi: 10.4095/223767. Geological Survey of Canada, Open File 5529.