Calcite Pseudomorphs after Ikaite From Washoe Co., Nevada

摘要

Ikaite, CaCO3 6H2O, is not only very rare, but it is also a very strange mineral. In collections it exists as a pseudomorph of the "thinolite" or "glendonite" variety of calcite, CaCO3. Ikaite is actually a hexahydrate of calcite with the H2O forming a lightly bound cage around the calcite molecule. The H2O is quickly lost °n the mineral through rapid dehydration, leaving a calcite Pseudomorph of the original Ikaite. The name comes from the Ikka Fjord on the southwest coast of Greenland where a discovery was made in 1963 (Pauly, 1963).