gemstone

Banded agate (likely a small polished agate cabochon)

Microcrystalline quartz, chiefly SiO₂; banding is chalcedony with contrasting mineral inclusions or layers

AI-generated identification · may be incorrect

Polished, rounded stone with pale gray-white and dark gray/black bands. Quartz hardness 6.5–7 Mohs; vitreous to waxy luster, cryptocrystalline structure, no visible cleavage; specific gravity about 2.6.

Identified October 5, 2026More gemstone →

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At a glance

Common name: Banded agate (likely a small polished agate cabochon)
Scientific name: Microcrystalline quartz, chiefly SiO₂; banding is chalcedony with contrasting mineral inclusions or layers
Category: gemstone
Identified: October 5, 2026
Method: Standard

AI Estimated Value

About $2–$15 USD for a small common polished cabochon; higher value requires verified quality, workmanship, or provenance.

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

Agate forms as silica-rich fluids deposit successive layers in cavities, commonly in volcanic rocks; the specimen’s geological age and exact source cannot be determined from the photo. The reported Tamil Nadu location is regionally plausible for quartz and agate-bearing material, though not enough to establish provenance.

Uses & applications

Used for jewelry, beads, cabochons, ornaments, and collecting; this small piece appears shaped and polished for jewelry or craft use.

Geological facts

Agate’s bands record changing silica deposition conditions; some bands become visible only after cutting and polishing.

Field identification & locations

Look for curved or parallel bands, a smooth polish, and hardness sufficient to scratch glass; visual identification alone cannot rule out dyed or imitation material. Similar agates occur worldwide, including India.