mineral

Quartz (specifically Milky/Yellow Quartz)

Silicon Dioxide (SiO2)

Hardness: 7 (Mohs scale); Color: Pale yellow to off-white; Luster: Vitreous to waxy; Crystal structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific gravity: 2.65

Hardness: 7 (Mohs scale)
Color: Pale yellow to off-white
Luster: Vitreous to waxy

Identified March 25, 2026More mineral →

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Physical properties

Hardness: 7 (Mohs scale); Color: Pale yellow to off-white; Luster: Vitreous to waxy; Crystal structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific gravity: 2.65

Formation & geological history

Formed through the cooling of silica-rich magma or from hydrothermal veins. It is one of the most abundant minerals in the Earth's crust, found in virtually all geological ages from Precambrian to recent times.

Uses & applications

Used in glass manufacturing, electronics (due to piezoelectric properties), abrasives, and as decorative gravel or inexpensive gemstones in jewelry.

Geological facts

Quartz is so chemically and physically stable that it is the primary component of most beach sand. The yellow tint often comes from trace amounts of iron or microscopic fluid inclusions.

Field identification & locations

Identify in the field by its ability to scratch glass and its lack of cleavage. It is commonly found in riverbeds, mountains, and as garden stones. For collectors, look for clarity and crystal faces, though this specimen is water-worn or tumbled.

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