The Sleeper deposit presents the opportunity to study the details of gold (and silica) depositional processes over a wide vertical interval, extending from depths of 500m to almost the original paleosurface. The proposed research consists of 1) detailed (band-scale) isotopic, trace-element geochemical, and textural studies of the shallow banded ore to document the isotopic and geochemical signature of the ore-forming fluids; 2) studies of deep veins, which will include fluid inclusion, isotopic, mineralogic, textural, and trace-element geochemical analyses. The data generated should provide input for thermochemical modeling, which should in turn provide tests of hypotheses formulated to explain salient features of the banded high-grade ore at the Sleeper deposit. Results will provide new insights into gold depositional processes in shallow epithermal vein systems and how the processes change with depth. It also will refine existing genetic and exploration models for these vein systems.