A Mn occurrence/prospect/mine located in sec. 15, T12S, R24E, MDM, 4.4 km (2.7 miles) WSW of Trimmer, on the SW slope of Hog Mountain. MRDS database stated accuracy for this location is 500 meters.

Mineralization is lenses and beds of very dense rhodonite and quartz rhodonite rock interbedded with thin-bedded cherts and shales. It is partially oxidized to black manganese oxides. The black oxide beldongrite is thought to be present. These beds are part of a series of dynamically metamorphosed cherts, shales, and tuffs. Associated rocks include dunite and pyroxenite. Local rocks include ultramafic rocks, chiefly Mesozoic, unit 2 (Western Sierra Nevada and Klamath Mountains).

Workings include unspecified surface openings/operations.

Very little good oxide ore has been developed and no commercial ore could be profitably obtained.

Select Mineral List Type

Standard Detailed Gallery Strunz Chemical Elements

Mineral List

ⓘ 'Beldongrite' ?

ⓘ 'Manganese Oxides'

ⓘ Rhodonite

1 valid mineral.

Detailed Mineral List:

ⓘ 'Beldongrite' ?

Formula: Mn₁₈Fe₂O₃₃ · 8H₂O

Description: Thought to be present.

References:

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

ⓘ 'Manganese Oxides'

References:

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

ⓘ Rhodonite

Formula: CaMn₃Mn[Si₅O₁₅]

References:

Taliaferro, Nicholas Lloyd & A.J. Solari (1943a), Manganese deposits of the Sierra Nevada: their genesis and metamorphism: California Division Mines and Geology Bulletin 125: 327

Trask, Parker Davies, Ivan F. Wilson & F.S. Simons (1943), Manganese deposits of California – a summary report: California Division Mines Bulletin 125: 112

Trask, Parker Davies (1950) Geologic description of the manganese deposits of California. California Division of Mines Bulletin 152, 378 pp.: 53-55.

Gallery:

List of minerals arranged by Strunz 10th Edition classification

Group 9 - Silicates
ⓘ	Rhodonite	9.DK.05	CaMn₃Mn[Si₅O₁₅]
Unclassified
ⓘ	'Beldongrite' ?	-	Mn₁₈Fe₂O₃₃ · 8H₂O
ⓘ	'Manganese Oxides'	-

List of minerals for each chemical element

H	Hydrogen
H	ⓘ Beldongrite	Mn₁₈Fe₂O₃₃ · 8H₂O
O	Oxygen
O	ⓘ Beldongrite	Mn₁₈Fe₂O₃₃ · 8H₂O
O	ⓘ Rhodonite	CaMn₃Mn[Si₅O₁₅]
Si	Silicon
Si	ⓘ Rhodonite	CaMn₃Mn[Si₅O₁₅]
Ca	Calcium
Ca	ⓘ Rhodonite	CaMn₃Mn[Si₅O₁₅]
Mn	Manganese
Mn	ⓘ Beldongrite	Mn₁₈Fe₂O₃₃ · 8H₂O
Mn	ⓘ Rhodonite	CaMn₃Mn[Si₅O₁₅]
Fe	Iron
Fe	ⓘ Beldongrite	Mn₁₈Fe₂O₃₃ · 8H₂O

Other Databases

Link to USGS MRDS:	10033449

Other Regions, Features and Areas containing this locality

North AmericaContinent

North America PlateTectonic Plate

Foothills-Wallowa DomainDomain
Sierra Nevada BatholithVolcanic Arc

USA

Sierra NevadaMountain Range

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References

(n.d.) Minerals Availability System (MAS), U.S. Bureau of Mines.file ID #0060190211

Taliaferro, Nicholas Lloyd & A.J. Solari (1943a), Manganese deposits of the Sierra Nevada: their genesis and metamorphism: California Division Mines and Geology Bulletin 125: 327

Trask, Parker Davies, Ivan F. Wilson & F.S. Simons (1943), Manganese deposits of California – a summary report: California Division Mines Bulletin 125: 112

Trask, Parker Davies (1950) Geologic description of the manganese deposits of California. California Division of Mines Bulletin 152, 378 pp.: 53-55.

Logan, Clarence August, Lewis T. Braun & James W. Vernon (1951), Mines and mineral resources of Fresno County, California: California Journal of Mines and Geology (Report 47): 47(3): 195, Pl. 1.

Murdoch, Joseph; Webb, Robert Wallace (1966) Minerals of California, Centennial Volume (1866-1966) - California Division of Mines and Geology, Bulletin 189. California Division of Mines and Geology. 559 pp.

Pemberton, H. Earl (1983) Minerals of California. Van Nostrand Reinhold Company Inc.

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

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