metamorphic

Greenstone, likely serpentine or green jasper

Serpentine-group minerals, chiefly antigorite/lizardite; possibly quartz-rich jasper

AI-generated identification · may be incorrect

Small tumbled, opaque to weakly translucent green pebble with a waxy surface and mottled pale-green color. Likely hardness about 2.5–5.5 Mohs, with no visible cleavage; exact properties require testing.

Identified August 8, 2026More metamorphic →

Explore Greenstone, likely serpentine or green jasper 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

Serpentine forms when ultramafic mantle rocks hydrothermally alter, commonly during oceanic-crust or mountain-building processes; jasper forms from silica-rich chemical sediments. Geological age depends on locality and cannot be determined visually.

Uses & applications

Used as a decorative stone, carving material, lapidary cabochons, and inexpensive jewelry; serpentine is also used architecturally, though fibrous varieties may contain asbestos and require care.

Geological facts

“Greenstone” is a broad trade term, not a precise identification; similar pebbles may be jade, aventurine, prehnite, chrysoprase, or dyed material.

Field identification & locations

Check streak, hardness, density, and polish: serpentine is usually soft and waxy, while jade is tougher and denser; a quartz scratch test can help. Common sources include California, Italy, New Zealand, Canada, and New England.