Vote for your favorite mineral in #MinCup26! - Sphalerite vs. Anorthite
Both zinc ore Sphalerite and calcium plagioclase feldspar Anorthite have perfect cleavage that will split cleanly if you hit them with a hammer, but only one can claim a larger split of your votes!
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Pioneer Mine, Napa County, California, USAi
Regional Level Types
Pioneer MineMine
Napa CountyCounty
CaliforniaState
USACountry

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Latitude & Longitude (WGS84):
38° North , 122° West (est.)
Estimate based on other nearby localities or region boundaries.
Margin of Error:
~41km
GRN:
N26W69
Type:
Mine
Köppen climate type:
Csb : Warm-summer Mediterranean climate
Mindat Locality ID:
18759
Long-form identifier:
mindat:1:2:18759:7
GUID (UUID V4):
0


A former Hg mine.

Select Mineral List Type

Standard Detailed Gallery Strunz Chemical Elements

Mineral List


2 valid minerals.

Detailed Mineral List:

ⓘ Mercury
Formula: Hg
References:
Dana 6:23.
ⓘ Quartz
Formula: SiO2
References:
Dana 6:23.

Gallery:

List of minerals arranged by Strunz 10th Edition classification

Group 1 - Elements
ⓘMercury1.AD.05Hg
Group 4 - Oxides and Hydroxides
ⓘQuartz4.DA.05SiO2

List of minerals for each chemical element

OOxygen
Oⓘ QuartzSiO2
SiSilicon
Siⓘ QuartzSiO2
HgMercury
Hgⓘ MercuryHg

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

Dana, Edward Salisbury; Dana, James Dwight (1892) A System of Mineralogy (6th ed.). John Wiley & Sons, Inc.
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