mineral

Beach Quartz Pebble

Quartz (Silica - SiO2)

Hardness: 7 on Mohs scale; Color: Milky white to tan/yellow due to iron inclusions; Luster: Vitreous to waxy (smooth from water erosion); Crystal Structure: Hexagonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65.

Hardness: 7 on Mohs scale
Color: Milky white to tan/yellow due to iron inclusions
Luster: Vitreous to waxy (smooth from water erosion)

Identified March 21, 2026More mineral →

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Physical properties

Formation & geological history

Formed through hydrothermal processes or within igneous rocks (like granite) millions of years ago, later eroded by rivers and wave action into a smooth, rounded beach pebble. Most beach quartz dates back several hundred thousand to millions of years depending on the local bedrock source.

Uses & applications

Common quartz is used in construction (sand/aggregate), glass making, and as an abrasive. Smooth pebbles like this are popular for home decor, landscaping, and lapidary tumbling for beginners.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. These rounded shapes are created through 'attrition,' where rocks crash against one another in the surf, wearing down sharp edges over centuries.

Field identification & locations

Identify by its hardness (it will scratch glass) and its smooth, egg-like shape found on coastlines. It lacks the internal grains of sandstone. Commonly found on almost every beach globally where tectonic or volcanic activity has introduced quartz veins.