A hexahydrate of the same molecular formula form towers in fjords, ikaite, while a clear version of this mineral is called Iceland spar.
This mineral gives its name to a "compensation depth" in the ocean, and one of its polymorphs occurs in gallstones and converts to it in the presence of water at low temperatures, vaterite. A hexahydrate of the same molecular formula form towers in fjords, ikaite, while a clear version of this mineral is called Iceland spar. A mineral often called its poor cousin may twin repeatedly to form "flowers of iron;" that mineral is aragonite. For 10 points, name this famously birefringent mineral of Mohs hardness three, the most common type of calcium carbonate on earth.
This mineral gives its name to a "compensation depth" in the ocean, and one of its polymorphs occurs in gallstones and converts to it in the presence of water at low temperatures, vaterite.
{Calcite} [prompt on {calcium carbonate} before mentioned]