A Geoscience Digital Image Library

DescriptionPrehnite, Ca2Al2Si3O10(OH)2 (calcium aluminum silicate hydroxide), is an attractive mineral and is occassionally used for ornamental stone purposes. Typical prehnite forms rather thick crusts with a rough or crystaline texture. Other similar minerals include gyrolite, smithsonite and hemimorphite. Prehnite is harder than these and lacks smithsonites luster. Prehnite can be associated with many nice minerals and can make a fine specimen on its own. This sample is roughly 6 cm in length.
LocationUSA ▹ Montana. Near Ennis.
PhotographerNessa Eull. 2002-02-20.
CollectionUniversity of North Dakota Mineralogy Collection #1260.
Key wordsPrehnite, Montana
Tech details397 KB. Hand specimen. Fujifilm FinePix S1Pro digital camera; 60mm AF Nikon micro lens.
GeoDIL number2391