Tumbled milky quartz

Hardness 7 Mohs; translucent cream-white color, vitreous to waxy luster, and conchoidal fracture. It has a trigonal crystal structure but no visible cleavage; specific gravity is about 2.65.

Quartz crystallizes from silica-rich igneous, metamorphic, and hydrothermal fluids; its cloudy appearance commonly results from microscopic fluid inclusions or fractures. The rounded shape indicates human tumbling and polishing, not a natural rock form.

Used as an inexpensive lapidary, craft, and decorative stone; clear varieties are used in jewelry and industry. This small tumbled piece has modest collector value.

Milky quartz is among the most common quartz varieties and may occur as veins, pegmatites, or massive aggregates. It can scratch ordinary window glass and steel, but not corundum or diamond.

Identify it by its white translucency, glassy appearance, lack of cleavage, and ability to scratch glass; avoid confusing it with calcite, which is softer and cleaves readily. Common worldwide, especially in quartz veins and granitic terrains.