gemstone

Tumbled red chalcedony or dyed agate

Microcrystalline quartz (SiO₂), likely chalcedony/agate; vivid color may be dye-enhanced

AI-generated identification · may be incorrect

Typically Mohs 6.5–7, vitreous to waxy luster, translucent to opaque, and no visible cleavage; rounded pieces show conchoidal fractures and may have subtle banding. The saturated crimson color and uneven patches suggest dyed material rather than naturally red chalcedony.

Identified August 22, 2026More gemstone →

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Physical properties

Formation & geological history

Chalcedony forms when silica-rich groundwater fills cavities and fractures, commonly in volcanic rocks; agate develops layered or banded silica deposition. Formation ages vary widely, often from the Cenozoic to older volcanic sequences.

Uses & applications

Used for beads, cabochons, carvings, decorative stone, and lapidary practice; lower-grade dyed pieces have modest jewelry and collector value.

Geological facts

Dyed chalcedony commonly concentrates color in cracks, pits, or surface zones, and may release color with harsh solvents. Natural red varieties include carnelian, but they are usually orange-red to brownish rather than intensely magenta.

Field identification & locations

Common sources include Brazil, Uruguay, India, Madagascar, and China. Test hardness against glass, inspect for banding and dye concentration, and avoid treating the glossy appearance alone as evidence of natural color.