文摘
Contemporary mineralogy and geochemistry are concerned with understanding and deciphering processes that occur near the surface of the Earth. These processes are especially important for resolving ecological challenges and developing principles of good environmental management. Selenium oxysalts, selenites and selenates, are relatively rare as minerals; there are presently only 34 known mineral species. Thirty-one “pure” selenites, which contain only selenite anionic groups, are known to occur naturally. The other three minerals each contain two anionic groups: selenate and selenite (schmiederite), selenate and sulphate (olsacherite), and selenate and iodate (carlosruizite).