A piece of Canada Balsam is placed in between two specimens of this mineral to create the Nicol Prism.
A piece of Canada Balsam is placed in between two specimens of this mineral to create the Nicol Prism. Ancient ooids (oh-oy-ds) are often composed from the "seas" of this substance that characterize the Paleozoic and the early Mesozoic Eras. The rock onyx is often confused for the "banded" form of this mineral found in Mexican mines. The highly unstable polymorph vaterite is converted to this mineral when it is exposed to water at low temperature. Erasmus Bartholin first observed "double (*) refraction" in a variety of this mineral known as Iceland spar. Aragonite is a polymorph of this mineral which can be found in mineral springs. For 10 points, Limestone is made of what mineral that has a value of "3" on the Mohs scale of hardness, and is composed of calcium carbonate?
A piece of Canada Balsam is placed in between two specimens of this mineral to create the Nicol Prism.
calcite