Chemical Formula: KCaSi8O20(F,OH).8H2O

Chemical Name: Potassium Calcium Silicate

Mineral Class: Phyllosilicate

Mineral Notes: The name of the mineral means "to leaf apart" in Greek. It was given because crystals tend to peel or flake apart when heated due to the loss of water. It forms as a secondary mineral in basalts. The mineral was redefined as a group name for the Fluorapophyllite, Natroapophyllite and Hydroxyapophyllite in 1978. However the extreme difficulty in individual identification means that many of these sub-species continue to be referred to under the generic name.

Description: Several well-fomed crystals of white Apophyllite on a basalt matrix and associated with Calcite. The Apophyllite crystals are mostly distorted four-sided prisms with pyramidal terminations. The waxy luster against the glassy Calcite combine to make this a very attractive display specimen.

Location: Nassik Quarry, Poona, India.