This should really read siver mines. Prosperity at Gold Hill was sustained for a period of 20 years between 1868 and 1888 by mining the Comstock Lode, a major deposit of silver ore. Mines such as the Yellow Jacket, Crown Point, and Belcher brought in over $10 million each in dividends.
The Comstock Lode was the first major U.S. deposit of silver ore, discovered under what is now Virginia City, Nevada on the eastern slope of Mt. Davidson, a peak in the Virginia range