Prehnite Mineral Specimen ~ Colorado ~ 3.2 oz is a hydrated calcium aluminum silicate mineral that typically forms stalactitic or botryoidal (grape-like) aggregates and is commonly found in shades of pale to dark green, though it can also be colorless, blue, or orange. Named after the Dutch Colonel Hendrik Von Prehn, who discovered it in the 18th century, prehnite is prized for jewelry and collecting . It has a hardness of 6-6.5 on the Mohs scale, a vitreous to pearly luster, and a translucent to transparent appearance. ** WE HAVE MANY BEAUTIFUL MINERAL SPECIMENS FROM THE USA AROUND THE GLOBE ** MOST ARE FROM OUR VARIOUS TRIPS ** ** SEE ENTIRE STORE FOR AMAZING MINERALS ** ** OUR GOAL IS TO MAKE COLLECTING FUN AFFORDABLE FOR ALL WITH GREAT LOW PRICING * #437