A nice cluster of apple-green prehnite crystals. Prehnite typically occurs in igneous and metamorphic rocks, and also in veins and cavities as a result of hydrothermal activity. 
 
Prehnite's green colouration comes from the inclusion of minerals such as iron.
 
Dimensions 2.69 x 1.89 x 2.71 inches
 
Weight: 173 grams