El Paso Mine, Franklin Mountains (Franklin Range), El Paso County, Texas, USAi

Regional Level Types
El Paso Mine	Deposit
Franklin Mountains (Franklin Range)	Mountain Range
El Paso County	County
Texas	State
USA	Country

A Sn-W occurrence/mine located 9 miles (15 km) N of El Paso, on private land. Discovered in 1899. Produced during the period 1909-1912. The USGS MRDS database accuracy for this locality is not stated.

Mineralization is a Sn-W deposit (Mineral occurrence model information: Model code: 47; USGS model code: 15b; Deposit model name: Sn veins), hosted in granite. The ore body is pinch and swell, strikes E-W to N65W and dips nearly vertically at a width of 0.61 meter (2 feet) and a length of 396.24 meters and a depth-to-top of 0 meters. Six veins occur nearly parallel to the mountain front that pinch out upward and downward. Local alteration includes scattered silicification, chloritization, and tourmalinization. Associated rocks include the Neoproterozoic Red Bluff Granite. Local rocks include granite.

The host rock contains microcline, plagioclase, tourmaline, and zircon and has an average Sn content of 0.0005%. Red Bluff Granite was recognized to be one of the youngest Precambrian intrusions in the Franklin Mountains. It is late Proterozoic, approximately 950 million years old. Romarchite (SnO) was reported in microcline pegmatite, but the data do not support a definite identification. The Bureau of Economic Geology's X-ray diffraction of heavy-mineral separates of samples from the same locality indicates the presence of cassiterite, fluorite, pyrite, and topaz, but no romarchite.

Workings include surface and underground openings comprised of open cuts and a 50 foot shaft. Pure Sn metal was produced at a small smelter built on site.

Prodced $ $6,813.00 (period values) of Sn metal.
Alteration: Scattered Silicification, Chloritization, Tourmalinization

Deposit: Six veins nearly parallel to the mountain front that pinch out upward and downward. This record incorporates data from duplicate mrds record no. D001353 by james e. Elliot (73 06) which has been deleted.

Deposit type: Sn veins

Geology: The host rock contains microcline, plagioclase, tourmaline, and zircon and has an average tin content of 0.0005%. Red bluff granite was recognized to be one of the youngest precambrian intrusions in the franklin mountains. It is late proterozoic, approximately 950 m.y. Old. Romarchite (sno) was reported in microcline pegmatite, but the data do not support a definite identification. The bureau of economic geology's x-ray diffraction of heavy-mineral separates of samples from the same locality indicates the presence of cassiterite, fluorite, pyrite, and topaz, but no romarchite.

Rock formation(s): Red Bluff Granite

Other Databases

Link to USGS MRDS:	10085695

Other Regions, Features and Areas containing this locality

References