gemstone

Polished purple chalcedony (likely lavender agate)

Microcrystalline quartz, SiO₂; chalcedony variety, possibly naturally iron- or manganese-colored

AI-generated identification · may be incorrect

Mohs hardness 6.5–7; translucent lavender-purple color, waxy to vitreous luster, cryptocrystalline quartz structure, no visible cleavage, specific gravity about 2.60–2.65. The smooth rounded form indicates tumbling or polishing; the dark mark may be a fracture, inclusion, or surface damage.

Identified August 14, 2026More gemstone →

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At a glance

Common name: Polished purple chalcedony (likely lavender agate)
Scientific name: Microcrystalline quartz, SiO₂; chalcedony variety, possibly naturally iron- or manganese-colored
Category: gemstone
Identified: August 14, 2026
Method: Standard

AI Estimated Value

About $5–$30 for a common polished palm stone; $30–$150+ for unusually vivid, translucent, patterned, or collectible material.

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 when silica-rich groundwater fills cavities and fractures in volcanic rocks, commonly building layered chalcedony or agate over long periods, generally in Cenozoic to older volcanic environments. This specimen is human-shaped and polished.

Uses & applications

Used for cabochons, beads, carvings, decorative stones, and lapidary display; its value depends on color uniformity, translucency, patterning, and finish.

Geological facts

Purple chalcedony is often marketed as lavender agate, grape agate, or amethyst chalcedony, though names may be commercial rather than strictly mineralogical.

Field identification & locations

Identify by its glass-scratching hardness, waxy appearance, fine texture, and lack of cleavage; common sources include Brazil, Uruguay, Madagascar, India, and Indonesia. A gemological test is needed to distinguish it from dyed quartz, glass, or purple fluorite.