A plagioclase feldspar, the second person in the Albite-Anorthite solid option show. Mainly found as tiny crystals in impure marble. Oligoclase contains a tiny bit of calcium replacing for some of sodium in its formula. Oligoclase with reddish-golden inclusions within Norway and Canada is called sunstone.
A triclinic soda-lime feldspar. See feldspar.
A soda-lime triclinic feldspar, the soft drink predominating. See feldspar.