A precious opal deposit located in sec 1, T38N, R24E, MDM, at Willow Creek, eastern side of the Calico Hills, several km north of the Little Joe Mine, on private land (?). Directions: 13 miles north of Gerlach Nevada on Highway 34, then 35 miles north on Soldier Meadow road in the Calico Hills. Previously owned by the Berchtold Family. The mining claims lapsed and could not be relocated due to a mineral withdrawal for the Black Rock Desert Wilderness.

The opal is formed in cavities within basalt.

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.

ⓘ Gemstones

ⓘ Mineral specimens

Mineral List

ⓘ Opal

ⓘ var. Precious Opal

1 valid mineral.

Detailed Mineral List:

ⓘ Opal

Formula: SiO₂ · nH₂O

References:

Castor, Stephen B., Ferdock, Gregory C. (2004) Minerals of Nevada. Special Publication 31. Nevada Bureau of Mines and Geology

ⓘ Opal var. Precious Opal

Formula: SiO₂ · nH₂O

References:

Castor, Stephen B., Ferdock, Gregory C. (2004) Minerals of Nevada. Special Publication 31. Nevada Bureau of Mines and Geology

Gallery:

List of minerals arranged by Strunz 10th Edition classification

Group 4 - Oxides and Hydroxides
ⓘ	Opal	4.DA.10	SiO₂ · nH₂O
ⓘ	var. Precious Opal	4.DA.10	SiO₂ · nH₂O

List of minerals for each chemical element

H	Hydrogen
H	ⓘ Opal	SiO₂ · nH₂O
H	ⓘ Opal var. Precious Opal	SiO₂ · nH₂O
O	Oxygen
O	ⓘ Opal	SiO₂ · nH₂O
O	ⓘ Opal var. Precious Opal	SiO₂ · nH₂O
Si	Silicon
Si	ⓘ Opal	SiO₂ · nH₂O
Si	ⓘ Opal var. Precious Opal	SiO₂ · nH₂O

Other Regions, Features and Areas containing this locality

North AmericaContinent

North America PlateTectonic Plate

Columbia Basin and RangeWide Rift
Shoofly-Olds Ferry DomainDomain
Southeast Oregon–Northern California BasinsBasin

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References

www.blackrockdesert.org (n.d.) https://www.blackrockdesert.org/wiki/index.php/Royal_Rainbow_Opal_Mine

www.holeystones.com (n.d.) http://www.holeystones.com/mining/gerlach.html

Vanderhoff, Mark (2002), Finding opals in the rough, Reno Gazette-Journal, 11-Sep-2002.

Castor, Stephen B., Ferdock, Gregory C. (2004) Minerals of Nevada. Special Publication 31. Nevada Bureau of Mines and Geology

Wentzell, Christopher (2020), personal communication to Mindat.org.

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