The latter naturally has higher levels of Aluminium and is more conducive to uses where Aluminium is not a deleterious element. Most of our trade is conducted in electrolytic grades of cones, turnings and lumps from Russia. Customers include the lead industry where Ca is used for deoxidising and the Magnesium industry where it is used in master alloys.
China possesses electrolytic production dating from the 1960s Sino-Soviet Pact. Some of these plants have been the last to be privatised due to the fact that Calcium is often used in the nuclear arena and thus Calcium production has remained under government control.
Calcium is classed as hazardous for transport and good attention should be paid to packing.
A typical grade of good quality electrolytic calcium metal would be – Ca 99% min, Al – 0.08%, Cu – 0.01% max, Mg – 0.08% max, Fe – 0.01% max, Mn – 0.015% max, N – 0.05% max, Sr – 0.2% max.
Calcium is a silvery-white, relatively soft metal that is obtained by heating calcium oxide (CaO) with aluminium metal in a vacuum. Although calcium metal is attacked by oxygen and water, the bulk metal is protected by an oxide-nitride film and can be worked as a metal.
Many minerals contain calcium. Calcium minerals are very common and can be mined anywhere. It is chiefly obtained from limestone, dolomite and gypsum. Common calcium-bearing minerals include anhydrite (calcium sulfate), gypsum (hydrated calcium sulfate), and aragonite or calcite (calcium carbonate).
Relative atomic mass