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Ch. 3: Precious Gem stones in 1903

Ch. 3: Precious Gem stones in 1903 Page of 130 Ch. 3: Precious Gem stones in 1903 Text size:minus plus Restore normal size   Mail page  Print this page
PRECIOUS STONES.
975
SAN DIEGO TOUK-MALINE MINING COMPANY. TOURMALINE.
The mines are situated in the east half of sec. 17, T. 11 S., R. IE., San Bernardino meridian, and about 1 miles northwest from Mesa Grande post-office. This property was opened by Mr. Gail Lewis at the time of the first discoveries on this mountain. He had but small success at first, but persevered and reached a fine pocket of gem material just before his option expired. The mine has been developed more elaborately than any other of the district and carried much deeper. Fine gem tourmalines are taken out at a depth of nearly 200 feet, the greatest depth at which these gems are obtained anywhere in the world. A tunnel 1:20 feet long was run, tapping the ledge at 61 feet; from this, drifts were run about 150 feet in both directions, and the ledge matter was stoped to the surface; tourmalines in paying quantities were then extracted. Later a tunnel was run 286 feet in length, tapping the ledges at from 115 to 170 feet, and drifts from 20 to 30 feet long were run on two ledges which were struck. The ledge matter is a finegrained pegmatite, showing on both top and bottom black tourmalines in fan-shaped crystallizations. Near the center, at intervals, pockets occur in which fine gem tourmalines are found, though not as rich as in the adjoining claim, the Himalaya, just described. This companjhas employed from 3 to 7 men continuously, and is doing good work, timbering the workings as they are made and doing scientific mining. The compaiw has its own lapidary in San Diego, where most of their product is cut. Wood, water, and all facilities are at hand. Giant powder has been used exclusivehT, and the blasting has not resulted in the breaking or destroying of an}- crystals. The ledges are over 18 inches in width and are generally of a character which would not be prospected, looking barren and worthless, but the locality seems to be highly mineralized, and any ledge shows gem crystals.
Other mines are being opened in the vicinity, and probably during li)05 there will be a great development in the Mesa Grande section. One recent opening may be noted in particular.
E.S.UEKALDA MINE.
TOURMALINE.
The Esmeralda mine is situated about 5 miles northwest of the Mesa Grande store and li miles west of the Himalaya mine, on the eastern slope of the Temescal \alle3-. It was located by Mr. Dougherty late in 1903 or early in 1901, and covers 1,500 by 600 feet. The course of the ledge is northeast and southwest, but the claim lies across a spur running southwest and northeast at right angles with the main ledge at an altitude of about 3,500 feet. The work consists of two open cuts crossing the vein and exposing it to a depth of 7£ feet; a tunnel of 60
Ch. 3: Precious Gem stones in 1903 Page of 130 Ch. 3: Precious Gem stones in 1903
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US Geol. Surv. 1904. Gemstones, Metals.
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