Orthoclase is an important igneous rock forming tectosilicate mineral. It is also known as alkali feldspar and is common in granite and related rocks.

Orthoclase is a name based on the Greek for "straight fracture," because its two cleavages are at right angles to each other. Orthoclase crystallizes in the monoclinic crystal system.

Orthoclase is a common constituent of most granites and other felsic igneous rocks and is often found in huge crystals and masses in pegmatite veins. It is used in the manufacture of porcelain and as a constituent of scouring powder.

Adularia (from Adular) is found in low temperature hydrothermal deposits. When pearly and opalescent, orthoclase is called moonstone and is used in jewelry. These opalescent varieties are known to be an intergrowth of orthoclase and albite called perthite. A glassy kind of orthoclase, called sanidine, is typical of felsic volcanic rocks and is found in the trachytes of the Drachenfels, Germany.

Associated Minerals are quartz, plagioclase feldspars, micas, garnets, tourmalines and topaz.

Orhtoclase can be confused with apatite, chrysoberyl,citrine,precious beryl, prehnite,topaz and zircon.

Color	It can be colored white, gray, yellow or red; rarely green.
Refractive Index	1.518-1.524
Pleochroism	N/A
Chemistry	Potassium Aluminum Silicate
Hardness	6
Density	2.56-2.58
Crystal Group	Monoclinic
Ocurrence	Salzburg, Austria; Cornwall, England and New York, Vermont, Maine and New Hampshire, USA.

Orthoclase helps us to become more heart-centered and more grounded.

The pictures above only represents the general appearance of the Orthoclase. Please note that the real Orthoclases in our stock will be of varied shapes, color and sizes.