A Hg-Cr occurrence located 5.4 km (3.3 miles) WNW of Calistoga Hot Springs. (MRDS database states that it is a Hg occurrence but cites shipment of Cr ore.)

Mineralization is hosted in serpentinite.

Local structures include local fractures.

About 85 tons of ore assaying 43 to 50% Cr203 was shipped.

Select Mineral List Type

Standard Detailed Gallery Strunz Chemical Elements

Mineral List

ⓘ Cinnabar

ⓘ Opal

2 valid minerals.

Detailed Mineral List:

ⓘ Cinnabar

Formula: HgS

References:

(2005) Mineral Resources Data System (MRDS), US Geological Survey.

ⓘ Opal

Formula: SiO₂ · nH₂O

References:

(2005) Mineral Resources Data System (MRDS), US Geological Survey.

Gallery:

List of minerals arranged by Strunz 10th Edition classification

Group 2 - Sulphides and Sulfosalts
ⓘ	Cinnabar	2.CD.15a	HgS
Group 4 - Oxides and Hydroxides
ⓘ	Opal	4.DA.10	SiO₂ · nH₂O

List of minerals for each chemical element

H	Hydrogen
H	ⓘ Opal	SiO₂ · nH₂O
O	Oxygen
O	ⓘ Opal	SiO₂ · nH₂O
Si	Silicon
Si	ⓘ Opal	SiO₂ · nH₂O
S	Sulfur
S	ⓘ Cinnabar	HgS
Hg	Mercury
Hg	ⓘ Cinnabar	HgS

Other Regions, Features and Areas containing this locality

North AmericaContinent

Coast MountainsMountain Range

North America PlateTectonic Plate

California Coast RangesAccretionary Complex
Franciscan DomainDomain

USA

California
- Mayacamas MountainsMountain Range
- Napa County
  - Calistoga Mining District (Silverado Mining District)Mining District

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References

Yates, Robert G. & Lowell S. Hilpert (1946), Quicksilver deposits of eastern Mayacmas district, Lake and Napa Counties, California: California Journal of Mines and Geology, California Division of Mines (Report 42): 42: 231-286

Averill, Charles V. (1947a), Mines and mineral resources of Lake County: California Journal of Mines and Geology, California Division Mines (Report 43): 43(1): 33.

Holmes, Jr., G.W. (1965), Mercury in California: in: U.S. Bureau of Mines Information Circular 8252

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