The Bates Hunter Mine, a historic shaft mine, is located in Gilpin County, Colorado, about 35 miles west of Denver, in the historic Central City mining zone. Central City is Colorado's oldest and most prominent mining region in the Front Range mineral belt. The mine itself covers 22 acres and has several well-established gold veins and is known for being a bates hunter gold mine.
Exploring Gold Rush in Colorado and a New Mining Era
Idaho Springs, Colorado, was the site of a gold discovery in January 1859. It was discovered some months later near Central City, Colorado, and became renowned as the "Richest Square Mile on Earth." Miners extracted 113.40 tonnes (4 million ounces) of gold and 3345.24 tonnes (118 million ounces) of silver from the area a few decades later. We're ready to start up where the old-timers left off here at the Bates Hunter Mine, 160 years after the first finding of gold in Colorado. In 1934, just before the mine's previous closure, the mine's last mine manager wrote a remarkable historical report.
At a depth of 227.08 m, there was still high-grade gold in the sill (745 ft). At the bottom of the Bates and other nearby mines, old assays claim more than 5 opt, Au, with equally spectacular results at depths of up to 670.56 m (2200 ft). All we have to do now is de-water the mine, rehab it, and bring everything up to MSHA standards for the twenty-first century. By no means an easy task, but one that is well worth the effort and the opportunity to add a new mining operation to Colorado's network.
Mineralogy and Geology
The Bates Hunter Mine is located in the northeastern portion of the Colorado Mineral Belt, in the foothills of the Rocky Mountains. It is made up of thousands of feet of interlayered gneisses created from Precambrian country rock that has been metamorphosed and distorted. Intrusive dikes, pegmatites, fractures, and faults littered the area during the Laramide Orogeny around 60 million years ago, providing an excellent host for hydrothermal fluids to flow through and emplace today's ore deposits, which are primarily extracted for their high gold content. Before going through an obvious vein structure, the change is always visible for several feet.
The alteration is frequently QSP (Quartz, Sericite, Pyrite), with a vein concentration of quartz gangue and sulphide metallics, most commonly pyrite, chalcopyrite, chalcocite, sphalerite, galena, and, on rare occasions, visible gold. With the naked eye, just around 15% of the gold is visible. Even though the adjoining stringers to the Bates vein are modest, ranging in size from a few inches to a few feet, they exhibit powerful Au values, often exceeding 1 opt Au.
Fortunately for us, the USGS did an exhaustive study in 1963 on behalf of the US Atomic Energy Commission, resulting in USGS reports 359 and 474C, which concentrated on the central city mining region and provided us with an ample and reliable resource from which to learn and create.
Many studies and publications on the possibilities of mineral production date back to the late 1800s at the Central City Mining District and the Bates Hunter Mine. It's no secret that gold was extracted here and that it was expected to generate much more in the future, but the mine has been closed since the late 1930s.
The mine is now serviced by infrastructure that would cost around $40 million to recreate today. It features an elevator that can service the whole "main" shaft, which is about 800 feet long. It has its mill to process the tonnes of "rock" that will be extracted and processed before being shipped to a smelter. It is equipped with an EPA-approved water filtration system. Experts have their eyes on bates hunter gold mine.