mineral

Quartz Pebble

Quartz (Silicon Dioxide, SiO2)

Hardness: 7 on Mohs scale; Color: Milky white to translucent with iron staining (orange/brown); Luster: Vitreous to waxy (when water-worn); Crystal Structure: Hexagonal (trigonal); Cleavage: Indistinct/Conchoidal fracture; Specific Gravity: 2.65.

Hardness: 7 on Mohs scale
Color: Milky white to translucent with iron staining (orange/brown)
Luster: Vitreous to waxy (when water-worn)

Identified June 27, 2026More mineral →

Identify your own rocks.

Get a report just like this from any photo, free.

App Store Google Play

Physical properties

Formation & geological history

Formed from silica-rich hydrothermal veins or crystallizing from cooling magma. This particular specimen is a water-worn pebble, likely eroded from a vein and polished by river or beach transport over thousands of years.

Uses & applications

Used in glass manufacturing, electronics (piezoelectric properties), abrasives, and as semi-precious gemstones for jewelry and lapidary work.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. It is highly resistant to chemical and physical weathering, which is why it often survives as pebbles long after other minerals have turned to clay.

Field identification & locations

Identify in the field by its hardness (it should scratch glass), conchoidal fracture, and lack of cleavage. Common in riverbeds, beaches, and gravel pits worldwide.