Description: Potassium Feldspar, also called Orthoclase, also referred as “pink” feldspar, is found in many igneous granites and pegmatites, and metamorphic gneisses. It is the mineral assigned a hardness of "6" in the Moh's hardness scale.

Color: Colorless to white, greenish-white, grayish-yellow, and pale pink

Streak: White

Luster: Vitreous, Sub-Vitreous, Resinous

Fracture: Irregular, uneven, conchoidal

Cleavage: One perfect cleavage and one good cleavage intersecting at 90° (right angles)

Hardness: 6

Density/Specific Gravity: 2.55 - 2.63 g/cm³

Distinguishing Physical Properties:

• Cleavage: Perfect, with cleavage faces intersecting at right angles

• Lack of fine parallel striations that characterize the plagioclase minerals

• Color: Potassium feldspars commonly have pink to reddish hues, while the plagioclase feldspars tend to be white or gray, but again, color is not a perfect diagnostic tool