mineral

Clear Quartz (Double Terminated)

Silicon Dioxide (SiO2)

Hardness: 7 on the Mohs scale; Color: Colorless and transparent; Luster: Vitreous (glassy); Crystal Structure: Hexagonal (trigonal); Cleavage: None (conchoidal fracture); Specific Gravity: 2.65.

Hardness: 7 on the Mohs scale
Color: Colorless and transparent
Luster: Vitreous (glassy)

Identified March 29, 2026More mineral →

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Physical properties

Hardness: 7 on the Mohs scale; Color: Colorless and transparent; Luster: Vitreous (glassy); Crystal Structure: Hexagonal (trigonal); Cleavage: None (conchoidal fracture); Specific Gravity: 2.65.

Formation & geological history

Formed through the cooling of silica-rich magma or precipitation from hydrothermal veins. This specific double-terminated shape often forms in soft matrix or pockets where the crystal can grow freely at both ends without being attached to a rock wall.

Uses & applications

Used in the electronics industry for its piezoelectric properties, glass manufacturing, optical equipment, and widely as gemstones in jewelry and decorative specimens for collectors.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Double-terminated crystals like this one are often referred to as 'Herkimer Diamonds' when found in specific locations in New York, though this is a misnomer as they are quartz, not diamond.

Field identification & locations

Identify in the field by its six-sided prism shape and hardness (it will scratch glass). Common locations include the Swiss Alps, Brazil, Madagascar, and Arkansas, USA. When collecting, look for intact points and high clarity.

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