gemstone

Carnelian (orange-red chalcedony)

Chalcedony, microcrystalline quartz (SiO₂), iron-colored variety

AI-generated identification · may be incorrect

Translucent orange to reddish-brown, waxy to vitreous luster, cryptocrystalline structure, no visible cleavage, conchoidal fracture; Mohs hardness 6.5–7; specific gravity about 2.60. The rough, naturally fractured surface suggests an unpolished specimen.

Identified August 10, 2026More gemstone →

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Physical properties

Formation & geological history

Forms when silica-rich groundwater fills cavities and fractures, with iron oxides producing the orange-red color. Chalcedony is commonly Cenozoic to older, and this material is geologically plausible around Hungary’s volcanic and sedimentary terrains, though the exact locality cannot be determined visually.

Uses & applications

Used for beads, cabochons, carvings, seals, and ornamental stone; rough pieces are popular among collectors. Common specimens are modestly priced.

Geological facts

Carnelian is a variety of chalcedony rather than a separate mineral species. Heating can intensify its red-orange color, and it may grade into brown jasper or agate.

Field identification & locations

Test for hardness against steel or glass, inspect for translucent edges and conchoidal fracture, and distinguish it from orange calcite by its greater hardness and lack of cleavage. Common sources include India, Brazil, Uruguay, Madagascar, and central Europe.