3.45" Polished Blue Caribbean Calcite "Moon"

Caribbean Calcite, also marketed under the name "Blue Aragonite", is a blue calcite and aragonite formation that resembles a Caribbean coastline in its brown and blue coloration. It comes from a carbonate mineral deposit discovered in 2019 along the border of Pakistan and Afghanistan in the Balochistan region. The blue-colored mineral is calcite, while the white-brown material is aragonite.

Calcite and aragonite are two different forms of calcium carbonate. Calcite is the stable form, whereas aragonite is metastable. When heated over a long time period, aragonite will ultimately transform into calcite.