PETROGRAPHIC ANALYSIS OF MINERALIZED AND NON-MINERALIZED SAMPLES ALONG THE CARLIN TREND OF NORTHEASTERN NEVADA

The Railroad District mining area is located southwest of Elko Nevada. It is located within the corridor known as the Carlin Trend, where some of the most lucrative gold mines are in production today. The focus of this study is to characterize the mineralized and non-mineralized host rocks using petrographic analysis followed by detailed chemical analysis. Host rocks consist of the Devonian Devils Gate Limestone, and Mississippian Web Mudstone, and the Chainmen Sandstone Formations. The majority of the mineralized samples in this study are from fault breccia zones surrounding formations. Preliminary data was gathered using an Environmental Scanning Electron Microscope (ESEM) with an energy dispersive X-ray spectroscopy attachment (EDAX). Traverses were taken across selected minerals and associated matrix. Traverses across mineralized samples indicate that an average of 18.78% of a 573 μm line is mineralized rock with an average of 2 wt. % gold and upwards of 4.5 wt. % in some areas. Other proxy elements such as Ba, S, Fe, Na, K, Tl, Cd, and As have been correlated with specific minerals which potentially house the gold.