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
Ore Mountains this is a contract between Boresch of Riesenburg and the Ossegg abbot, Gerwig, in which the division of revenue derived from ore was agreed. Grains of tin ("Zinnkörner" or "Graupen") were obtained at that time in the Seiffen mining area and gave the Bohemian mining town of Graupen (Czech "Krupka") its name. With the further settlement of the Ore Mountains in the 15th century, new, rich, ore deposits were eventually discovered around Schneeberg Annaberg and St. Joachimsthal. The "Second Berggeschrey" started and triggered a massive wave of colonization. In quick succession, new, planned, mining towns were built across the Ore