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: A large cluster of white Apohyllite. The crystals are well-formed and have clean edges and terminations. The largest crystal shows a cubic habit but two of the faces tend to octahedral form. The mineral has a very strong glassy luster and shows some transparency. A striking display specimen.

Location: Phalaborwa, Transvaal, South Africa.