East Tintic Mining District, East Tintic Mountains, Utah County, Utah, USAi

Regional Level Types
East Tintic Mining District	Mining District
East Tintic Mountains	- not defined -
Utah County	County
Utah	State
USA	Country

The East Tintic district, in Utah County 30 mi southwest of Provo, is a subdistrict of the greater Tintic mining area, the second largest district in Utah. East Tintic is a very large Ag-Pb-Au producer and was productive from the early 1900s to the 1970s. The district is about the fifth largest metal mining district in Utah. Total district metal production at modern metal prices is estimated at $3.14 billion. Nearly 6 million tons of ore have been mined from the East Tintic district averaging recovered grades of about 435 ppm Ag, 3.77 ppm Au, 8.5% Pb, 3.0% Zn, and minor amounts of Cu as well as by-product Cd, Bi, and Mn (Krahulec and Briggs, 2006). The district is the third largest Zn producer in Utah. The Burgin Pb-Zn-Ag and the Tintic Standard Ag-Pb underground mines are the two most productive operations.
The East Tintic district is located on the Deep Creek–Tintic mineral belt of the Basin and Range Province in central Utah. Geologically, the district is structurally complex. The thrust-cored East Tintic anticline is unconformably overlain by Eocene- Oligocene volcanic rocks of the East Tintic volcanic field and intruded by Oligocene (~33 Ma) monzonite plugs, andesite porphyries, and numerous pebble dikes. Most of the historical production from the East Tintic subdistrict was derived from Paleozoic sedimentary-rock hosted, vein and replacement deposits (USGS Model 19a) in the upper plate of the East Tintic thrust, except for the Burgin mine in the lower plate (Morris and others, 1979). Some of the deposits, like the Trixie, which are in less reactive quartzite or shale, are generally more Cu-rich with high-sulfidation mineral assemblages with enargite and luzonite (USGS Model 25e).
East Tintic displays a broad pattern of metal zoning, ranging from higher-temperature Cu-Au-Fe in the southwest, through Pb- Ag, to cooler Zn-Mn mineralization in the northeast. The surficial hydrothermal alteration pattern in the volcanic rocks of the district reflects a similar pattern with the most intense and pervasive advanced argillic alteration in two areas in the southwest near the North Lily shaft and a larger one to the south covering Big Hill (Krahulec and Briggs, 2006).
The East Tintic district, like Southwest Tintic, potentially represents a high level lithocap over a deeply buried porphyry Cu (-Mo) system. Intrusions, mineralization, and pervasive porphyry-style alteration are focused in the two areas of advanced argillic alteration.