mineral
Quartz (Milky or Chalcedony)
Silicon Dioxide (SiO2)
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.
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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.
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