Prehnite
Pronunciation : Prehn"ite
Part of Speech : n.
Etymology : [So called from the German Colonel Prehn, who first found it.] (Min.)
Definition : Defn: A pale green mineral occurring in crystalline aggregates having a botryoidal or mammillary structure, and rarely in distinct crystals. It is a hydrous silicate of alumina and lime.
Source : Webster's Unabridged Dictionary, 1913