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Feldspar

Metal

Feldspar

Feldspar

Two series of alumino-silicate minerals that are important class of rock forming minerals. The two series are the plagioclase feldspars in which form a continuous solid solution series between the sodium (albite) and calcium (anorthite) rich end members, and the alkali feldspars with a full range of solid solutions between the sodium (albite) and potassium (orthoclase) end members. However, there is only a limited range of solid solubility between orthoclase (potassium) and anorthite (calcium) members. The last component to freeze in many slags have compositions that are close to the composition of anorthite or more rarely orthoclase/leucite.