Beresovite

(named after the Berezov formation in the Urals), a rock consisting of quartz (25–50 percent), albite (5–25 percent), sericite (10–15 percent), and carbonate (0–10 percent). It is rich in pyrite and shot through with quartz veins (occasionally ore veins). Beresovite forms as a result of low-temperature metasomatic changes in granites under the influence of hydrothermal solutions of the acidic stage of leaching. Beresovite and beresovitic rocks are indicative of deposits of gold and other ores.