In October 1850, George Knight made the discovery of gold-bearing quartz on Gold Hill that sparked the great excitement leading to the development of quartz mining into a major California industry. Although gold-bearing quartz had undoubtedly been noticed there and elsewhere at about the same time or earlier, this discovery became the one associated with the beginning of quartz mining in California. From 1850 to 1857, the Gold Hill Mine was credited with a total production of $4,000,000.00.