An ORE is the naturally occurring form of a particular element, from which the element can be EXTRACTED and further purified for commercial or other uses.
So, Bauxite is the principal ORE of aluminium in NATURE. It is a clay-like mineral, being a mixture of hydrated oxides and hydroxides. An example is (Al(OH)3)
Thus, Alcoa controlled the supply of bauxite in the United States before the World War II IN ORDER TO ensure the continuous availability of aluminum
The law of conservation of mass states that mass is neither created nor destroyed by chemical reactions or physical transformations. according to this, the mass of the products must equal the mass of the reactants.