metamorphic
Tumbled serpentinite (likely)
Serpentinite; chiefly serpentine-group minerals (antigorite, lizardite, chrysotile), commonly with magnetite and carbonate
AI-generated identification · may be incorrectDark olive-gray, mottled and waxy to dull luster with pale veining; typically massive rather than visibly crystalline. Hardness is about 2.5–4 Mohs, with variable specific gravity around 2.5–2.6; the image alone cannot confirm composition.
Identified More metamorphic →
Explore Tumbled serpentinite (likely) in the encyclopedia →Identify your own rocks.
Get a report just like this from any photo, free.
Physical properties
Dark olive-gray, mottled and waxy to dull luster with pale veining; typically massive rather than visibly crystalline. Hardness is about 2.5–4 Mohs, with variable specific gravity around 2.5–2.6; the image alone cannot confirm composition.
Formation & geological history
Forms when ultramafic mantle rocks such as peridotite hydrate during hydrothermal alteration, commonly along plate boundaries and subduction zones. Ages range from Precambrian to modern tectonic settings.
Uses & applications
Used as decorative stone, polished collectibles, carvings, and occasionally architectural facing; fibrous chrysotile-bearing material should not be cut or abraded because of asbestos risk.
Geological facts
Its characteristic green-black “snakeskin” pattern reflects serpentine minerals and magnetite. It may be confused with jasper, soapstone, or altered basalt.
Field identification & locations
Likely identification requires a hardness test, streak, density, and ideally thin-section or X-ray analysis; common localities include California, Italy, New Zealand, Canada, and the Alps. Avoid inhaling dust from unknown specimens.
More like this
