mineral and organic gemstone

Turquoise and Spiny Oyster (Heishi style beads)

Turquoise (CuAl6(PO4)4(OH)8·4H2O) and Spondylus (Spiny Oyster shell)

AI-generated identification · may be incorrect

Turquoise: Hardness 5-6 (Mohs), sky blue to greenish-blue, waxy to sub-vitreous luster, triclinic crystal system. Spiny Oyster: Calcite/Aragonite composition, hardness 3.5-4, vibrant red/orange/purple hues, pearly to dull luster.

Identified March 24, 2026More mineral and organic gemstone →

Explore Turquoise and Spiny Oyster (Heishi style beads) 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: Turquoise and Spiny Oyster (Heishi style beads)
Scientific name: Turquoise (CuAl6(PO4)4(OH)8·4H2O) and Spondylus (Spiny Oyster shell)
Category: mineral and organic gemstone
Identified: March 24, 2026
Method: Standard

AI Estimated Value

$15-$60 for a standard strand of commercial-grade beads; $100-$500+ for high-quality, hand-cut, designer or vintage Native American necklaces.

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

Turquoise forms as a secondary mineral in the oxidation zone of copper deposits through hydrothermal precipitation. Spiny Oyster is an organic gemstone formed by marine bivalve mollusks primarily in the Gulf of California.

Uses & applications

Primarily used in jewelry, particularly in Native American (Navajo, Zuni, Santo Domingo) lapidary arts such as Heishi beads and inlay work. Highly valued by collectors of Southwestern art.

Geological facts

This combination of turquoise and shell is traditional to the Pueblo peoples of the American Southwest; the blue represents the sky and water, while the red/orange represents the earth or fire. The turquoise shown appears to be 'stabilized' or 'matrixed' commonly used in bead making.

Field identification & locations

Identify turquoise by its characteristic Robin's egg blue and dark matrix (limonite or sandstone). Identify Spiny Oyster by its striations and vibrant natural pigments. Common in the US Southwest, Mexico, and Iran. Collectors should look for smoothness of the drill holes and color consistency.