Serpentine

Physical Properties

Hardness: 3–6 on Mohs scale; Color: typically green to yellowish-green with mottled streaks; Luster: waxy to greasy; Crystal Structure: Monoclinic; Cleavage: poor; Specific Gravity: 2.5–2.6.

Formation & Geological History

Formed through 'serpentinization,' a low-temperature metamorphic process where ultramafic rocks from the Earth's mantle are hydrated. Typically occurs at tectonic plate boundaries and subduction zones.

Uses & Applications

Used as ornamental stone for carvings, architectural veneers, and historically as a source of asbestos. Used in lapidary work for jewelry and 'fake jade' decorative items.

Geological Facts

Serpentinite is the official state rock of California. The name comes from the green color and scaly appearance, which resembles the skin of a serpent.

Field Identification & Locations

Identify in the field by its distinctive green, mottled color, waxy feel, and softness (it can often be scratched with a copper penny or steel knife). Found commonly in mountain belts like the Appalachians, Alps, and Coast Ranges.

Identified on: 4/20/2026

Mode: Standard