Orthoclase crystals, a selection of specimens of this crystallized mineral species. Orthoclase is a mineral, also called orthoclase in French, and adularia is a variety. Here you’ll find a number of collector’s items presented with a description, one or more photos and sometimes a video. These orthoses and adularia are for sale.
It’s a silicate, subgroup of the tectosilicates, family of potassium feldspars, with chemical formula KAlSi3O8, and monoclinic crystal system.