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
Lateritic nickel ore deposits It is bound in newly formed phyllosilicate minerals. All the nickel in the silicate zone is leached downwards (absolute nickel concentration) from the overlying goethite zone. Typical nickel laterite ore deposits are very large tonnage, low-grade deposits located close to the surface. They are typically in the range of 20 million tonnes and upwards (this being a contained resource of 200,000 tonnes of nickel at 1%) with some examples approaching a billion tonnes of material. Thus, typically, nickel laterite ore deposits contain many billions of dollars of in-situ value of contained metal. Ore deposits of this type are restricted to