Vote for your favorite mineral in #MinCup26! - Quartz vs. Asagiite
It's a classic vs a newbie as the most common named mineral in the crust Quartz is up against an exceedingly-rare sea foam-green mineral discovered just a few years ago Asagiite.
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Sillimanite from
Dehesa Dumortierite deposit (Lehesa Dumortierite deposit), Alpine, Laguna Mountains, San Diego County, California, USA


Locality type:Deposit
Classification
Species:Sillimanite
Formula:Al2(SiO4)O
Comments:A constituent of dumortierite gneiss.
Confirmation
Validity:Believed Valid
Associated Minerals:
Associates:Dumortierite
Quartz
Data
Mineral Data:Click here to view Sillimanite data
Locality Data:Click here to view Dehesa Dumortierite deposit (Lehesa Dumortierite deposit), Alpine, Laguna Mountains, San Diego County, California, USA
Data Identifiers
Mindat Occurrence Record ID:668373
Long-form Identifier:1:3:668373:3
GUID (UUID V4):0
Nearest other occurrences of Sillimanite
1.1km (0.7 miles) ⓘMcCullough deposit (Unnamed Sillimanite occurrence), Alpine, Laguna Mountains, San Diego County, California, USA
6.9km (4.3 miles) ⓘDehesa, San Diego County, California, USA
67.1km (41.7 miles) ⓘUnnamed Sillimanite occurrence, Split Mountain Canyon, Split Mountain, San Diego County, California, USA
References
Kunz, George F. (1905) Gems, Jewelers' Materials, and Ornamental Stones of California. Bulletin 37 (2nd ed.) California State Mining Bureau
Schaller, Waldemar Theodore (1905) Dumortierite. American Journal Of Science, S. 4 Vol. 19. 211-224
Murdoch, Joseph & Robert W. Webb (1966), Minerals of California, Centennial Volume (1866-1966): California Division Mines & Geology Bulletin 189: 173, 338
 
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