metamorphic

Polished multicolored mineral pebble, possibly ruby-in-zoisite

Ruby-bearing zoisite (zoisite: Ca₂Al₃(SiO₄)₃(OH); ruby: corundum, Al₂O₃)

AI-generated identification · may be incorrect

Small rounded specimen with a green-gray matrix and a pink-red inclusion, consistent with ruby-in-zoisite; zoisite has Mohs hardness 6–7, while ruby is 9. Typically vitreous to waxy luster, granular texture, and no obvious cleavage.

Identified September 1, 2026More metamorphic →

Explore Polished multicolored mineral pebble, possibly ruby-in-zoisite 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: Polished multicolored mineral pebble, possibly ruby-in-zoisite
Scientific name: Ruby-bearing zoisite (zoisite: Ca₂Al₃(SiO₄)₃(OH); ruby: corundum, Al₂O₃)
Category: metamorphic
Identified: September 1, 2026
Method: Standard

AI Estimated Value

Approximately $2–$15 for a tiny common tumbled piece; $20–$100+ for larger, vividly colored polished specimens.

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 by metamorphism of aluminum- and calcium-rich rocks, commonly in East African deposits; geological ages vary by locality, often Precambrian. The rounded shape indicates tumbling or polishing rather than natural crystal faces.

Uses & applications

Used as a lapidary material for cabochons, beads, carvings, and decorative specimens; rarely used for high-value jewelry because the matrix is opaque and variable.

Geological facts

The red areas are ruby, the green matrix is zoisite, and black flecks may be hornblende or other accessory minerals. Strong color contrast is its defining visual feature.

Field identification & locations

Commonly identified by opaque green/gray zoisite containing contrasting pink-red ruby patches; a scratch test should not be used on a valuable specimen. Common sources include Tanzania and Kenya.