mineral

Carnelian Agate

Silicon Dioxide (SiO2) with iron oxide inclusions

Hardness: 6.5-7 (Mohs scale); Color: Red, orange, white, and brownish-red; Luster: Vitreous to waxy; Crystal structure: Trigonal/Microcrystalline; Cleavage: None (conchoidal fracture); Specific gravity: 2.58-2.64

Hardness: 6
Color: Red, orange, white, and brownish-red
Luster: Vitreous to waxy

Identified April 29, 2026More mineral →

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Physical properties

Formation & geological history

Formed in cavities and fissures of igneous rocks (basalts) where silica-rich groundwater deposits successive layers of microcrystalline quartz over thousands of years.

Uses & applications

Primarily used for decorative carvings, lapidary arts, jewelry, and as holistic or meditation crystals in the form of polished towers or points.

Geological facts

The vibrant orange-red color is caused by the presence of iron oxide (hematite). Many commercial carnelian specimens are actually dyed grey chalcedony or heat-treated to enhance their colors.

Field identification & locations

Identify by its characteristic rhythmic banding, translucency, and warm red-orange hues. Often found in Brazil, India, Madagascar, and Uruguay. In the field, look for volcanic host rocks or river gravels.

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Mineral/Rock

Banded Gneiss (River Rock/Pebble)

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Metamorphic Rock

Green Apatite on Albite

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mineral