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Unnamed Graphite-Wollastonite occurrences [1], Seahaven, Inverness Ridge (Point Reyes Hill), Point Reyes Cape, Marin County, California, USAi
Regional Level Types
Unnamed Graphite-Wollastonite occurrences [1]Group of Occurrences
SeahavenUnincorporated Community
Inverness Ridge (Point Reyes Hill)Ridge
Point Reyes CapeCape
Marin CountyCounty
CaliforniaState
USACountry

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Latitude & Longitude (WGS84):
38° 13' 1'' North , 122° 58' 48'' West (est.)
Estimate based on other nearby localities or region boundaries.
Margin of Error:
~0km
GRN:
N26W70
Type:
Group of Occurrences
Köppen climate type:
Csb : Warm-summer Mediterranean climate
Mindat Locality ID:
217703
Long-form identifier:
mindat:1:2:217703:1
GUID (UUID V4):
0


Occurrences located about 1½ miles NW of Inverness, on the W shore of Tomales Bay. NOTE: This description places these occurrences in or near Seahaven.

Select Mineral List Type

Standard Detailed Gallery Strunz Chemical Elements

Commodity List

This is a list of exploitable or exploited mineral commodities recorded at this locality.


Mineral List


4 valid minerals.

Detailed Mineral List:

ⓘ 'Apophyllite Group'
Formula: AB4[Si8O22]X · 8H2O
Colour: Colourless
Description: Occurs as transparent glassy crystals 1 to 2 mm in size in fissures of a quartzite.
ⓘ Calcite
Formula: CaCO3
ⓘ Graphite
Formula: C
ⓘ Tremolite
Formula: ◻Ca2Mg5(Si8O22)(OH)2
Description: Occurs in schists on the shore of the bay.
ⓘ Wollastonite
Formula: Ca3(Si3O9)
Description: Occurs as crystals and layers in schist.

Gallery:

List of minerals arranged by Strunz 10th Edition classification

Group 1 - Elements
ⓘGraphite1.CB.05aC
Group 5 - Nitrates and Carbonates
ⓘCalcite5.AB.05CaCO3
Group 9 - Silicates
ⓘTremolite9.DE.10◻Ca2Mg5(Si8O22)(OH)2
ⓘWollastonite9.DG.05Ca3(Si3O9)
Unclassified
ⓘ'Apophyllite Group'-AB4[Si8O22]X · 8H2O

List of minerals for each chemical element

HHydrogen
Hⓘ Apophyllite GroupAB4[Si8O22]X · 8H2O
Hⓘ Tremolite◻Ca2Mg5(Si8O22)(OH)2
CCarbon
Cⓘ CalciteCaCO3
Cⓘ GraphiteC
OOxygen
Oⓘ Apophyllite GroupAB4[Si8O22]X · 8H2O
Oⓘ CalciteCaCO3
Oⓘ Tremolite◻Ca2Mg5(Si8O22)(OH)2
Oⓘ WollastoniteCa3(Si3O9)
MgMagnesium
Mgⓘ Tremolite◻Ca2Mg5(Si8O22)(OH)2
SiSilicon
Siⓘ Apophyllite GroupAB4[Si8O22]X · 8H2O
Siⓘ Tremolite◻Ca2Mg5(Si8O22)(OH)2
Siⓘ WollastoniteCa3(Si3O9)
CaCalcium
Caⓘ CalciteCaCO3
Caⓘ Tremolite◻Ca2Mg5(Si8O22)(OH)2
Caⓘ WollastoniteCa3(Si3O9)

Other Regions, Features and Areas containing this locality

North AmericaContinent
North America PlateTectonic Plate

This page contains all mineral locality references listed on mindat.org. This does not claim to be a complete list. If you know of more minerals from this site, please register so you can add to our database. This locality information is for reference purposes only. You should never attempt to visit any sites listed in mindat.org without first ensuring that you have the permission of the land and/or mineral rights holders for access and that you are aware of all safety precautions necessary.

References

Walker, John A. (1885), Graphite: Mineral Resources of the US, 1883-84: 915-919.
Anderson, Frank M. (1899), The geology of Point Reyes peninsula: University of California, Department of Geological Science Bulletin: 2: 119-153.
Murdoch, Joseph & Robert W. Webb (1966), Minerals of California, Centennial Volume (1866-1966): California Division Mines & Geology Bulletin 189: 67, 80, 206, 387.
Pemberton, H. Earl (1983) Minerals of California. Van Nostrand Reinhold Company Inc.
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