metamorphic

Serpentinized ultramafic rock (serpentinite)

Serpentinite, dominated by serpentine-group minerals (antigorite, lizardite, chrysotile), commonly with magnetite and relict olivine/pyroxene

AI-generated identification · may be incorrect

Typically dark green, black, brown, or reddish, with waxy to greasy luster; Mohs hardness about 2.5–4. It commonly shows slickensides, veining, mottled textures, and locally fibrous or crystalline serpentine; the image’s green-yellow veins and dark altered matrix fit this well.

Identified September 15, 2026More metamorphic →

Explore Serpentinized ultramafic rock (serpentinite) in the encyclopedia →

Identify your own rocks.

Get a report just like this from any photo, free.

App Store Google Play

At a glance

Common name: Serpentinized ultramafic rock (serpentinite)
Scientific name: Serpentinite, dominated by serpentine-group minerals (antigorite, lizardite, chrysotile), commonly with magnetite and relict olivine/pyroxene
Category: metamorphic
Identified: September 15, 2026
Method: Standard

AI Estimated Value

$5–$30 for a common field specimen; roughly $30–$150 for attractive polished or well-patterned pieces.

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 mantle-derived peridotite is hydrated and metamorphosed, usually along tectonic plate boundaries and ophiolite belts. The specimen is likely Mesozoic or younger oceanic crust material exposed in the Coast Mountains of British Columbia.

Uses & applications

Used as decorative stone, carvings, and historically as a minor architectural stone; attractive specimens are collected. Avoid cutting or generating dust because some serpentinites may contain asbestos-form chrysotile.

Geological facts

The reported location near 49.3°N, 124.2°W is regionally plausible: Vancouver Island and coastal British Columbia contain altered ultramafic rocks and serpentinite. Yellow-green material may include weathered serpentine, chlorite, or iron-bearing alteration minerals.

Field identification & locations

Look for low density, green-black mottling, waxy surfaces, slickensides, and pale-green veins; it may scratch with a steel knife but not glass. A magnet can respond weakly to associated magnetite; laboratory testing is needed to distinguish it from epidote-rich rock or copper-bearing alteration.