mineral

Quartz (Rock Crystal)

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale; Color: Colorless/Transparent; Luster: Vitreous (glassy); Crystal Structure: Hexagonal (trigonal); Cleavage: Indistinct/Conchoidal fracture; Specific Gravity: 2.65.

Hardness: 7 on Mohs scale
Color: Colorless/Transparent
Luster: Vitreous (glassy)

Identified June 27, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: Colorless/Transparent; Luster: Vitreous (glassy); Crystal Structure: Hexagonal (trigonal); Cleavage: Indistinct/Conchoidal fracture; Specific Gravity: 2.65.

Formation & geological history

Formed primarily from the cooling and solidification of silica-rich hydrothermal fluids or magma. This specimen displays the transparency typical of rock crystal quartz, common in tectonic regions like the Huon Peninsula of Papua New Guinea.

Uses & applications

Used in jewelry, precision optics, electronics (as oscillators due to piezoelectric properties), and as a collector's item.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Pure quartz is known as rock crystal; and this specimen shows characteristic conchoidal fracturing on the right edge.

Field identification & locations

Identify in the field by its inability to be scratched by steel and its glass-like appearance without cleavage planes. The reported location (Lae/Morobe region) is geologically active with significant quartz deposits in volcanic and metamorphic terranes.