Mineral Species: Apophyllite
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 crystals of rare green Apophyllite on a basalt matrix and associated with white Mordenite. The Apophyllite crystals are mostly cubic but some form distorted four-sided prisms with square terminations. The gentle green colour and waxy luster make this a very attractive display specimen.
Location: Nassik Quarry, Poona, India.