mineral

Carnelian Agate

Chalcedony (SiO2) with iron oxide inclusions

Hardness: 6.5-7.0 (Mohs); Color: Orange, red-orange, translucent brown; Luster: Waxy to vitreous; Crystal Structure: Trigonal (microcrystalline); Cleavage: None (conchoidal fracture); Specific Gravity: 2.58-2.64

Hardness: 6
Color: Orange, red-orange, translucent brown
Luster: Waxy to vitreous

Identified April 18, 2026More mineral →

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Physical properties

Formation & geological history

Formed as a primary mineral in cavities of volcanic rocks or as veins in sedimentary environments. Its color is derived from iron oxide (hematite) impurities during the silica deposition process.

Uses & applications

Used primarily in jewelry making (cabochons, beads), decorative carvings, and as a popular semi-precious gemstone for collectors and metaphysical enthusiasts.

Geological facts

Carnelian was used by ancient Egyptians and Romans in signet rings and amulets because it does not stick to hot wax. It is one of the most historically significant colored gemstones, dating back to at least 4500 BC.

Field identification & locations

Identify by its characteristic 'banded' chalcedony appearance combined with warm orange/red hues. It is commonly found in Brazil, India, Uruguay, and Madagascar. In the field, look for nodules with a waxy exterior.

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Mineral/Rock

Banded Gneiss (River Rock/Pebble)

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Metamorphic Rock

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mineral