mineral

Quartz (Milky or Chalcedony)

Silicon Dioxide (SiO2)

AI-generated identification · may be incorrect

Hardness of 7 on the Mohs scale, white to translucent color, vitreous to waxy luster, trigonal crystal system, conchoidal fracture with no true cleavage, specific gravity of 2.65.

Identified August 2, 2026More mineral →

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Physical properties

Hardness of 7 on the Mohs scale, white to translucent color, vitreous to waxy luster, trigonal crystal system, conchoidal fracture with no true cleavage, specific gravity of 2.65.

Formation & geological history

Forms in a wide variety of geological environments, frequently crystallizing from silica-rich hydrothermal solutions or cooling magmas, often found in veins, pegmatites, and sedimentary rocks.

Uses & applications

Used in electronics, watchmaking, glass manufacturing, ornamental items, and lapidary arts.

Geological facts

Quartz is one of the most abundant minerals in the Earth's continental crust and exhibits piezoelectric properties, meaning it can generate an electrical charge in response to mechanical stress.

Field identification & locations

Can be identified by its high hardness (scratches glass), lack of cleavage, and conchoidal fracture. Found worldwide in nearly every type of geological environment.