metamorphic
Serpentine-rich rock (probable serpentinite)
Serpentinite; predominantly serpentine-group minerals, commonly antigorite, lizardite, or chrysotile, with possible magnetite and carbonate
AI-generated identification · may be incorrectTypically olive-green to brown with mottled or waxy surfaces and locally slick texture; Mohs hardness about 2.5–4, luster waxy to greasy, very fine-grained, with no obvious cleavage. The rounded shape and glossy surface may reflect natural weathering or polishing; image-based identification is provisional.
Identified More metamorphic →
Explore Serpentine-rich rock (probable serpentinite) in the encyclopedia →Identify your own rocks.
Get a report just like this from any photo, free.
Physical properties
Typically olive-green to brown with mottled or waxy surfaces and locally slick texture; Mohs hardness about 2.5–4, luster waxy to greasy, very fine-grained, with no obvious cleavage. The rounded shape and glossy surface may reflect natural weathering or polishing; image-based identification is provisional.
Formation & geological history
Forms when ultramafic mantle rocks such as peridotite hydrate during low-temperature metamorphism, commonly along faults and oceanic-plate boundaries. Serpentinite can range from Paleozoic to modern tectonic settings.
Uses & applications
Used as decorative stone, carvings, countertops, and collector specimens; historically used for tools and ornamental objects. Avoid cutting or sanding unknown material because some serpentinites may contain chrysotile asbestos.
Geological facts
Green coloration comes from serpentine minerals, while dark flecks may be magnetite or chromite and reddish areas may reflect iron oxidation. Serpentinite commonly feels unusually smooth or soapy.
Field identification & locations
Common in ophiolite belts and subduction-related mélanges, including California, the Appalachians, New Zealand, Italy, and the Urals. Confirm with a streak, hardness, magnetism, and ideally Raman/XRD testing; it could also be another green altered ultramafic rock.
More like this
