gemstone

Ruby (rough or poorly polished corundum)

Corundum, Al₂O₃; red gem-quality corundum is ruby

AI-generated identification · may be incorrect

Small translucent-to-opaque deep pink-red piece with a vitreous luster and irregular shape; corundum has Mohs hardness 9 and a trigonal crystal structure, with no true cleavage. The photo alone cannot confirm it is natural or distinguish ruby from dyed material or glass.

Identified October 13, 2026More gemstone →

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At a glance

Common name: Ruby (rough or poorly polished corundum)
Scientific name: Corundum, Al₂O₃; red gem-quality corundum is ruby
Category: gemstone
Identified: October 13, 2026
Method: Standard

AI Estimated Value

If natural ruby, roughly $1–$100 for a tiny low-grade fragment; treated or synthetic material may be worth under $1. High-quality faceted ruby can be vastly more valuable.

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

Natural ruby forms in aluminum-rich, silica-poor metamorphic rocks and some igneous deposits; many deposits are hundreds of millions to over a billion years old. Heat treatment and other processing are common in the gem trade.

Uses & applications

Faceted ruby is used in jewelry; synthetic ruby also serves in lasers, watches, and durable industrial components.

Geological facts

Ruby and sapphire are both corundum; trace chromium produces ruby’s red color.

Field identification & locations

Natural ruby commonly occurs in Myanmar, Mozambique, Madagascar, Sri Lanka, and Thailand. Confirm identity with gemological testing; a tiny, irregular, unverified fragment is not reliably identifiable from appearance alone.