Mexican onyx, onyx marble, oriental alabaster, alabaster - a hard compact kind of calcite

chalk - a soft whitish calcite

Iceland spar - a transparent calcite found in Iceland and used in polarizing microscopes

limestone - a sedimentary rock consisting mainly of calcium that was deposited by the remains of marine animals

calcium carbonate - a salt found in nature as chalk or calcite or aragonite or limestone

spar - any of various nonmetallic minerals (calcite or feldspar) that are light in color and transparent or translucent and cleavable