Pegmatites Research Papers - Academia.edu (original) (raw)

LOCATION 14S 5E Sec. 10 SBM 32.97505999980 -116.46334000000 (MRDS, 2011). This mine is in the Oriflamme Mountains 1.6 miles west-northwest of a mobile home park. Hilton’s article has a motor guide to access the prospect and a... more

LOCATION

14S 5E Sec. 10 SBM 32.97505999980 -116.46334000000 (MRDS, 2011).

This mine is in the Oriflamme Mountains 1.6 miles west-northwest of a mobile home park.

Hilton’s article has a motor guide to access the prospect and a description of Mrs. Mason’s gravesite. While lepidolite, tourmaline and other minerals were observed, his article concludes with this statement: “A tunnel over a hundred feet in length had been driven into the side of the hill, and we followed this to its end, but saw no evidence that the miners had encountered a crystallized section such as would indicate the presence of gems.”

The U.S.G.S. topographic map show prospects in the SW1/4 of Section 3 to the north of the MRDS location in Section 10. This topographic map also shows a tunnel and two adits near the center of Section 10.

GEOLOGY

This deposit is a pegmatite reported to contain lepidolite and tourmaline (Hilton, 1939, p. 26-28). It was listed by Tucker and Reed (1939) as a prospect (Tucker and Reed,1939, p. 55).

Dibblee (2008f) mapped the mine area as Mesozoic or older gneiss.

REFERENCES

Dibblee, T.W., 2008e, Geologic map of the Borrego and Borrego Mountain 15 minute quadrangles, San Diego and Imperial Counties, California, Dibblee Geological Foundation, Map DF-409, 1:62,500

Dibblee, T.W., 2008f, Geologic map of the Mount Laguna and Carrizo Mountain 15 minute quadrangles, San Diego and Imperial Counties, California, Dibblee Geological Foundation, Map DF-407, 1:62,500

Hilton, John, 1939, Mine that has everything except gemstones: Desert, vol. 3, no. I, p. 26-28, 35. (Tourmaline bearing pegmatitic deposit, Mason Valley area).

MRDS, 2011, Mineral Resources Data System, U.S. Geological Survey, https://mrdata.usgs.gov/mrds/. This database relies on records that are, in many cases, are inaccurate or imprecise. For example, if a report describes a mine as being in “Section 9”, with no other information, MRDS plots the mine location in the center of the section. If a mine is reported in “SW ¼” of a section, MRDS plots the mine in the center of that SW quarter-section.

Tucker,W. B., and Reed, C. H., 1939, Mineral resources of San Diego Country: California Div. Mines and Geology: XXXV Report of the State Mineralogist, Volune 35, p. 55 and Map.

Weber, F. Harold, 1963 Geology and Mineral Resources of San Diego County, California Division of Mines and Geology, Report 3, Deposit No. 111, p. 107.