Pink Moonstone
Orthoclase var. Moonstone · Semi-Precious Gemstone
Crystal System
Monoclinic; typically found in massive or tumbled forms as seen here, rather than distinct crystals.
Mineral Group
Silicates (Tectosilicates); Feldspar group
Chemical Formula
(K,Na)AlSi3O8 (Potassium Aluminum Silicate)
Formation Process
Igneous/Hydrothermal: Formed through the cooling of magma where orthoclase and albite separate into alternating layers (exsolution) during cooling.
About This Crystal
A tumbled, opaque to translucent stone with a dusty pink to flesh-toned body color. It exhibits a soft, vitreous to pearly luster and a characteristic shimmering surface effect.
Physical Characteristics
Color: Pinkish-tan; Streak: White; Cleavage: Two directions at nearly 90 degrees; Fracture: Conchoidal to uneven; Specific Gravity: 2.56-2.59; Tenacity: Brittle; Fluorescence: Occasionally weak blue or orange under UV.
Optical Properties
Displays adularescence (a glowing light effect) caused by light scattering between microscopic layers of feldspar. Refractive Index: 1.518-1.526; Birefringence: 0.005-0.008.
Hardness & Durability
Origin Region
Primarily India, Sri Lanka, Madagascar, and Tanzania; often found in alkaline pegmatites.
Hardness & Durability
Mohs Hardness: 6.0 - 6.5. Fair toughness; susceptible to cracking if struck hard due to perfect cleavage.
Care & Maintenance
Clean with warm soapy water and a soft brush. Avoid ultrasonic and steam cleaners. Sensitive to sudden temperature changes and harsh household chemicals.
Rarity & Value
Common to Uncommon. Value is determined by the strength of the adularescence (sheen) and clarity. Generally affordable as a tumbled stone or cabochon.
Special Characteristics
Adularescence (schiller effect) is the primary feature; this specific specimen shows a metallic-looking reflection or 'flash' across its surface grain.
Lore & History
Historically associated with lunar cycles and the Greek goddess Selene. In traditional lore, it is considered a stone of 'new beginnings,' inner growth, and emotional stability. It is often associated with the Heart and Crown chakras.