Heulandite Natural Display Crystal for Collectors. | 75x1.63x1.38" |Heulandite mineral specimen a hydrated calcium sodium aluminium silicate mineral that can be found in basalt cavities. Heulandite creates sprays of complex translucent crystals exhibiting soft color hues. Its colors range from clear to white, pink, yellow, green, grey, brown, and black. It can be vitreous or pearly, and it can exhibit a translucent to a transparent luster. Heulandite is often mistaken as Stilbite. August Breithaupt discovered the