Calcium Metal Properties
Calcium metal is never found in a natural state due to its chemical reactivity with oxygen.
The main components of sedimentary rock samples such as limestone, chalk, marble, and dolomite, as well as eggshells and pearls, are calcite formations. In addition, limestone is the most common source of metallic calcium production [1,2].
Calcium is used in lead refining (separation of bismuth), steel purification (desulfurization, deoxidation, and dephosphorization), and as an alloying agent for silicon and lead. Also, calcium can be used to recover refractory metals from their oxide form (e.g., chromium, rare earths, and thorium), for the reduction of uranium dioxide, and as an agent for the reduction of boron oxide [3,4,5].
1-Mantell, C.L. The alkaline earth metals: Calcium, barium, and strontium. In Rare Metals Handbook, 2nd ed.; Hampel, C.A., Ed.; Reinhold: New York, NY, USA, 1973; pp. 15–25.
2-Belitskus, D. Aluminothermic production of metals and alloys. JOM 1972, 24, 30–34.
3-Sokic, M.; Matković, V.; Marković, B.; Gulišija, Z.; Patarić, A.; Mihailović, M.; Janjušević, Z. The possibilities of obtaining metallic calcium from Serbian carbonate mineral raw materials. Chem. Ind. Chem. Eng. Q. 2014, 20, 397–405.
4-Liu, L.; Chen, M.; Xu, L.; Yin, X.; Sun, W. Effect of BaO Addition on Densification and Mechanical Properties of Al2O3-MgO-CaO Refractories. Metals 2016, 6, 84.
5-Giorgi, F.T.; Alexander, S. Production of Advanced Materials by Methods of Self-Propagating High-Temperature Synthesis; Springer: New York, NY, USA, 2013.