Description

Prehnite is a Phyllosilicate mixture of Calcium and Aluminum.  Although it is not a Zeolite, it is often associated with them and with Datolite and Calcite, in veins and cavities of Basaltic rocks, sometimes in Granites, Syenites or Gneisses.  The color varies from light green to grey to white to yellow or a mix of colors.  It is translucent and was named after its discoverer, Colonel Hendrik von Prehn.