Quartz (Citrine or Iron-stained Quartz)

Physical Properties

Hardness: 7 (Mohs scale); Color: Pale yellow to whitish; Luster: Vitreous (glassy); Crystal Structure: Hexagonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Formation & Geological History

Formed in igneous environments like pegmatites or hydrothermal veins from silica-rich solutions settling in rock cavities. Its coloration is often due to oxidized iron impurities or natural irradiation.

Uses & Applications

Commonly used in lapidary work for jewelry, as a healing crystal in metaphysical practices, and industrial uses in glass manufacturing or electronics due to its piezoelectric properties.

Geological Facts

Quartz is the second most abundant mineral in Earth's continental crust. If it is high-quality natural citrine, it is quite rare, though most commercial citrine is actually heat-treated amethyst.

Field Identification & Locations

Identify by its ability to scratch glass easily and the absence of cleavage. Look for the wavy, shell-like (conchoidal) fracture pattern where it has been broken. Found globally in mountainous regions.

Identified on: 4/27/2026

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