metamorphic

Possible serpentine or greenstone pebble

Serpentine-group minerals, chiefly antigorite/lizardite; exact identification requires testing

AI-generated identification · may be incorrect

Small rounded green-gray specimen with mottled coloration and likely dull to waxy luster. Serpentine has Mohs hardness 2.5–4, poor cleavage, and specific gravity about 2.5–2.6; the image is insufficient to confirm texture or composition.

Identified September 9, 2026More metamorphic →

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Physical properties

Formation & geological history

Serpentine forms when ultramafic mantle rocks such as peridotite undergo hydrothermal metamorphism, commonly during oceanic crust alteration or tectonic uplift. Its age depends on the host geological terrane.

Uses & applications

Used as ornamental stone, carvings, tile, and historically as a source of asbestos-group fibers; attractive pieces are collected, though fibrous material should not be cut or powdered.

Geological facts

Green mottling can also indicate chlorite-rich greenstone, epidote-bearing rock, or weathered basalt, so this identification is provisional.

Field identification & locations

Common in ophiolite belts and metamorphic terrains. Check for a waxy feel, low hardness, pale green streak, and reaction to a steel knife; avoid inhaling dust. Likely value: $1–$10 as a common small pebble, higher if polished or confirmed as attractive serpentine.