mineral

Likely tumbled quartz or calcite pebble

Quartz (SiO₂) or calcite (CaCO₃); exact identification requires testing

AI-generated identification · may be incorrect

Small rounded, pale peach-white specimen with a dull-to-waxy luster and granular surface. Quartz has Mohs hardness 7, no cleavage, and specific gravity 2.65; calcite is softer (Mohs 3), has perfect rhombohedral cleavage, and specific gravity 2.71.

Identified August 30, 2026More mineral →

Explore Likely tumbled quartz or calcite pebble in the encyclopedia →

Identify your own rocks.

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

App Store Google Play

Physical properties

Formation & geological history

Likely a naturally weathered or human-tumbled mineral pebble; quartz commonly forms in igneous and hydrothermal veins, while calcite forms in limestone, cavities, and hydrothermal deposits. The specimen’s geological age cannot be determined visually.

Uses & applications

Used chiefly as a decorative or lapidary stone; quartz is also important in glass, electronics, and abrasives, while calcite is used in cement, lime, and neutralizing acids. This example is mainly a low-cost collectible or craft stone.

Geological facts

A steel knife or glass-scratch test can distinguish them: quartz resists scratching, whereas calcite scratches easily. Vinegar produces weak fizz on calcite but not quartz.

Field identification & locations

Common worldwide in gravel deposits, veins, cavities, and sedimentary rocks; inspect for translucency, cleavage, and hardness. A definitive identification requires hardness, acid, or specific-gravity testing.