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April Fool claims (April Fool claim; Keegan; Manganese No. 1 and No. 4 claims), Owlshead Mts, Inyo Co., California, USA

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Latitude & Longitude (WGS84): 35° 52' 50'' North , 116° 46' 4'' West
Latitude & Longitude (decimal): 35.8805555556, -116.767777778
A Mn occurrence/group of claims located in sec. 33, T21N, R2E, SBM, 6.0 km (3.7 miles) WSW of Shore Line Butte (Death Valley), on the western margin of Death Valley in the "Owlshead Mountains," (32 miles by road W of Zobriskie, a station on the Tonopah and Tidewater Railway; 1 mile N of the low mountains immediately N of Owl Lake), on National Park Service wilderness land (Death Valley National Park/Death Valley Wilderness). MRDS database stated accuracy for this location is 1,000 meters.

Mineralization is hosted in conglomerate. The ore is low in specific gravity and is a porous, tuffaceous bog Mn ore with a maximum thickness of 18 inches (45 cm) at the April Fool claim. Thin layers of pink, clayey material gives the ore a decided bonded appearance. A sample analysis of the ore was 32.2% Mn and 30.2% insoluble. The Manganese No. 1 claim is ¼ mile SE of the April Fool, and what is thought to be the same Mn-bearing bed is exposed in the bed of a dry wash, with a maximum thickness of 30 inches. Ore analysis was 20.6% Mn and 42.2% insoluble. At the Manganese No. 4 claim, ¼ mile NE of the Manganese No. 1, a well-defined vein of hard, black metallic oxide and scattered boulders of waste rock, cut the conglomerate with a strike of N60W and dipping steeply to the N. The maximum thickness of the vein is 6 feet (2 meters), and is exposed for 25 feet along the strike. Local rocks include Tertiary volcanic flow rocks, unit 16 (Northern Mojave Desert).

Mineral List

10 entries listed. 10 valid minerals.

The above list contains all mineral locality references listed on 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 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.


Trask, Parker Davies, Ivan F. Wilson & F.S. Simons (1943), Manganese deposits of California – a summary report: California Division Mines Bulletin 125: 121.

Trask, Parker Davies (1950) Geologic description of the manganese deposits of California. California Division of Mines Bulletin 152, 378 pp.: 80-81.

Norman, L.A. & Richard M. Stewart (1951), Mines and mineral resources of Inyo County, California: California Journal of Mines and Geology (Report 47): 47(1): No. 179, p. 191.

Evans, James R., G.C. Taylor, and J.S. Rapp (1976) Mines and mineral deposits in Death Valley National Monument. California Division Mines and Geology Special Report 125: 1-61.

USGS (2005), Mineral Resources Data System (MRDS): U.S. Geological Survey, Reston, Virginia, loc. file ID #10033467 & 10188212.

U.S. Bureau of Mines, Minerals Availability System (MAS) file ID #0060270703.

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