New Almaden hydrothermal deposition of cinnabar from deep within the earth is found in a gangue of silica-carbonate rock formed locally by hydrothermal alteration of serpentine. The Guadalupe mine produced about 10% as much mercury as the New Almaden. There are several smaller mines in the mining district, but their ore production was not significant. The only significant quicksilver ore is cinnabar; other sulfides are present in small quantities. Mining, other than a single placer deposit of cinnabar, was underground. There is a high probability of undiscovered high-grade ore which could be found and exploited using modern techniques. Mining operations resulted in
Archibald C. Godwin 6'6" Godwin as an Indian agent, and Charles F. Winslow after visiting the area wrote that they were "under Mr. Godwin's complete control." There were hot springs on the property which later became known as "The Geysers", and Godwin built "The Geysers Resort Hotel" to encourage visitors. He discovered that his land possessed rich cinnabar ore deposits and in 1859 filed mining claims, which he had to defend in court as others disputed his right to mine quicksilver. Godwin obtained a legal license after passing exams and successfully represented himself in court in Santa Rosa. He became involved in local