mineral

Tumbled moonstone (likely)

Feldspar, likely orthoclase or plagioclase; composition varies, approximately (K,Na,Ca)(Al,Si)₄O₈

AI-generated identification · may be incorrect

Pale gray-white, polished and rounded, with a subdued sheen; feldspar hardness is about 6–6.5 Mohs and its crystal system is monoclinic or triclinic. The photo does not clearly show the blue-white adularescence typical of gem-quality moonstone, so identification is provisional.

Identified October 13, 2026More mineral →

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Physical properties

Formation & geological history

Feldspar crystallizes in igneous and metamorphic rocks; moonstone’s internal layers form through feldspar exsolution during cooling. These minerals occur in rocks of many geological ages.

Uses & applications

Tumbled pieces are used in jewelry, crafts, and collections; feldspar is also widely used in ceramics and glassmaking.

Geological facts

Moonstone’s characteristic floating glow, called adularescence, comes from light scattering between microscopic feldspar layers.

Field identification & locations

Check for a moving sheen under a point light and a hardness near 6; the image alone cannot confirm moonstone rather than another pale feldspar or stone. Feldspars occur worldwide, including India, Sri Lanka, Madagascar, and the United States.