Siberian-Urals Aluminium Company comprises 19 businesses involved in the production of a chemical compound that naturally in what crystalline polymorphic phase?
SUAL Group:  It comprises 19 businesses that are located in nine Russian regions and are involved in the production of bauxite, alumina, primary aluminium, silicon, semi-finished and finished aluminium products. Aluminium oxide: Aluminium oxide (British English) or aluminum oxide (American English) is a chemical compound of aluminium and oxygen with the chemical formula Al O . Aluminium oxide:  It occurs naturally in its crystalline polymorphic phase α-AlO as the mineral corundum, varieties of which form the precious gemstones ruby and sapphire.
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