Orthoclase – an important rock-forming mineral from the large feldspar group, valued by collectors and jewelers for its attractive palette of shades and characteristic vitreous luster. Its colors range from creamy white, delicate pink, and peach to sunny yellow, greenish, or it can be completely colorless. Orthoclase primarily forms in igneous rocks like granites and pegmatites, often creating large, well-faceted, sometimes transparent crystals.
Major significant deposits are found in Brazil, Madagascar, the USA (California, Colorado), India, Norway, and the Swiss Alps. Beyond its collector's value, orthoclase is used as a gemstone (especially its transparent yellow varieties or adularia, known as moonstone), and also in the production of ceramics and glass due to its physical properties. Historically, orthoclase has been associated with serenity and inner balance.
Its gentle energy is believed to promote clarity of thought, help establish a harmonious connection between mind and feelings, and support emotional stability during periods of change. This makes it an appealing choice for those who appreciate the natural beauty of minerals and seek a stone with calming associations.
Physical properties
Chemical formula
KAlSi₃O₈
Hardness
6
Crystal system
Monoclinic
Transparency
Transparent to Translucent
Luster
Vitreous (glassy), sometimes pearly on cleavage surfaces
Color
Colorless, white, gray, yellow, pink, reddish, greenish
Specific gravity
2.55 - 2.63
Varieties
Jewelry with this mineral
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