Many are found as minerals, the more important of such naturally occurring carbonates being cerussite (lead carbonate, PbC03), malachite and azurite (both basic copper carbonates), calamine (zinc carbonate, ZnCO 3), witherite (barium carbonate, BaCO 3), strontianite (strontium carbonate, SrC03), calcite (calcium carbonate, CaC03), dolomite (calcium magnesium carbonate, CaCO 3 MgCO 3), and sodium carbonate, Na 2 CO 3.
STRONTIUM [[[Symbol]] Sr, atomic weight 87.62 (0 = 16)], a metallic chemical element belonging to the alkaline earth group. It is found in small quantities very widely distributed in various rocks and soils, and in mineral waters; its chief sources are the minerals strontianite, celestine and barytocelestine.
The metal was detected in the mineral strontianite, found at Strontian in Argyllshire, by Cruikshank in 1787, and by Crawford in 17 9 0; and the discovery was confirmed by Hope in 1792 and by Klaproth in 1793.
Strontium carbonate, SrCO 3, found in the mineral kingdom as strontianite, is formed when a solution of a carbonate is added to one of a strontium salt.
It is a constituent of the minerals cerussite, malachite, azurite, spathic iron ore, calamine, strontianite, witherite, calcite aragonite, limestone, &c. It may be prepared by burning carbon in excess of air or oxygen, by the direct decomposition of many carbonates by heat, and by the decomposition of carbonates with mineral acids, M2C03+2HC1=2MCl-FH 2 O+CO 2.