mineral

Druzy Quartz

Quartz (Silicon Dioxide, SiO2)

Hardness: 7 on Mohs scale; Color: Clear to light smoky/grayish in this specimen; Luster: Vitreous (glassy); Crystal Structure: Hexagonal (trigonal); Cleavage: Indistinct/None; Specific Gravity: 2.65.

Hardness: 7 on Mohs scale
Color: Clear to light smoky/grayish in this specimen
Luster: Vitreous (glassy)

Identified March 26, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: Clear to light smoky/grayish in this specimen; Luster: Vitreous (glassy); Crystal Structure: Hexagonal (trigonal); Cleavage: Indistinct/None; Specific Gravity: 2.65.

Formation & geological history

Formed through the precipitation of silica-rich hydrothermal fluids or groundwater within cavities of rocks such as geodes or vugs. The 'druzy' effect refers to a coating of tiny crystals on a rock surface. Formation can occur across various geological ages.

Uses & applications

Predominantly used in jewelry (pendants and rings), decorative carvings, and as a popular specimen for mineral collectors due to its sparkling aesthetic. In industry, high-purity quartz is used for electronics and optics.

Geological facts

The word 'quartz' comes from the German 'Quarz'. Druzy crystals are highly valued for their 'carpet of stars' appearance when they catch the light. They are often dyed or coated with titanium (forming 'Aura Quartz') to create rainbow effects.

Field identification & locations

Identify in the field by its characteristic sparkling surface and high hardness (it will scratch glass). Commonly found in volcanic rocks, limestone, and hydrothermal veins. Tips: Look for pockets or cracks in basalt or limestone where crystals may have grown undisturbed.