metamorphic

Serpentinite (likely serpentinized ultramafic rock)

Serpentine-group minerals, chiefly lizardite, chrysotile, and/or antigorite; commonly derived from peridotite

AI-generated identification · may be incorrect

Typically dark green to black, mottled or veined, with a waxy to greasy luster and fine-grained texture; Mohs hardness about 2.5–5.5, poor cleavage, and specific gravity roughly 2.5–2.7. The pale green-gray patches and dark veining are consistent with serpentinization, though the image alone cannot confirm the identifi…

Identified September 3, 2026More metamorphic →

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At a glance

Common name: Serpentinite (likely serpentinized ultramafic rock)
Scientific name: Serpentine-group minerals, chiefly lizardite, chrysotile, and/or antigorite; commonly derived from peridotite
Category: metamorphic
Identified: September 3, 2026
Method: Standard

AI Estimated Value

About $5–$30 for a common hand specimen; $30–$150+ for attractive polished or collectible material.

Not an official valuation

AI estimate for general interest only — not an appraisal. Actual value depends on condition, provenance, and market demand. Verify with a professional before buying, selling, or insuring.

This identification was generated by AI and may contain errors. Verify important details before relying on them — and never use an AI result to judge whether a specimen is safe to handle. Read the full disclaimer

Physical properties

Formation & geological history

Forms when water chemically alters mantle-derived peridotite, commonly along tectonic plate boundaries and ophiolites; alteration may occur from the Paleozoic to the present depending on locality.

Uses & applications

Used as decorative and carving stone, countertops, landscaping material, and a source rock for some nickel, chromium, and asbestos minerals; avoid cutting or abrading unknown specimens because chrysotile may be present.

Geological facts

Often associated with talc, magnetite, chromite, and veined carbonate minerals. Magnetite produced during alteration can make some specimens weakly magnetic.

Field identification & locations

Look for green-black coloration, waxy surfaces, slickensides, mesh-like veining, and unusual density; a streak, hardness, acid, and magnetic test would help distinguish it from chlorite schist or mafic rock. Common in California, the Appalachians, New Zealand, Italy, and many ophiolite belts.