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Glaucophane from
Angel Island, Marin County, California, USA


Locality type:Island
Classification
Species:Glaucophane
Formula:◻Na2(Mg3Al2)Si8O22(OH)2
Comments:Extremely fine crystals.
Habit:Needle-like
Colour:Blue
Confirmation
Validity:Believed Valid
Data
Mineral Data:Click here to view Glaucophane data
Locality Data:Click here to view Angel Island, Marin County, California, USA
Data Identifiers
Mindat Occurrence Record ID:648102
Long-form Identifier:1:3:648102:5
GUID (UUID V4):0
Nearest other occurrences of Glaucophane
7.0km (4.3 miles) ⓘCalifornia Point (Point Munroe), Tiburon Peninsula, Marin County, California, USA
7.2km (4.5 miles) ⓘReed Station, Tiburon Peninsula, Marin County, California, USA
13.9km (8.6 miles) ⓘBerkeley Country Club, El Cerrito, Contra Costa County, California, USA
32.2km (20.0 miles) ⓘNicasio, Marin County, California, USA
44.8km (27.8 miles) ⓘTurtle Rock Quarry, Mount Diablo (Mt Diablo), Clayton, Contra Costa County, California, USA
66.5km (41.3 miles) ⓘValley Ford, Sonoma County, California, USA
66.7km (41.5 miles) ⓘEbabias Creek, Valley Ford, Sonoma County, California, USA
68.4km (42.5 miles) ⓘMelitta, Santa Rosa, Sonoma County, California, USA
72.0km (44.7 miles) ⓘCalaveras Valley, Santa Clara County, California, USA
74.5km (46.3 miles) ⓘCamp 9 deposit (Camp 9 Merchant; Cummings), Mendenhall Springs, Livermore Mining District (Tesla District), Alameda County, California, USA
References
Ransome, Frederick Leslie (1894) The geology of Angel Island, California. University of California, Department of Geol. Sci. Bulletin: 1: 193-234.p.206
Murdoch, Joseph & Robert W. Webb (1966), Minerals of California, Centennial Volume (1866-1966): California Division Mines & Geology Bulletin 189: 69
Pemberton, H. Earl (1983) Minerals of California. Van Nostrand Reinhold Company Inc.
 
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