Carnelian
Carnelian is a silicate mineral recognized among collectors for its crystal form and distribution.
Carnelian is a translucent orange to red-brown variety of chalcedony (microcrystalline quartz), valued since antiquity for beads, seals and cabochons.
About Carnelianextended article
Carnelian is a warm orange to red-brown variety of chalcedony — the microcrystalline form of quartz. Its glowing colour comes from finely dispersed iron oxides, and it has been treasured for jewellery, signet rings and carved seals since the ancient world.
Identifying carnelian
Carnelian is hard (about 7 on the Mohs scale, like all quartz), translucent, and takes a high polish. Its colour ranges from pale orange through deep red-brown; darker, browner material grades into the related variety sard. Natural carnelian often shows a cloudy or banded distribution of colour, while heat treatment — an old and accepted practice — can deepen pale agate into rich orange.
Where it is found
Fine carnelian comes from India (notably the Deccan basalts of Gujarat), Brazil, Uruguay, Madagascar and many other places where silica-rich fluids filled cavities in volcanic and sedimentary rocks.
For collectors and lapidaries
Even, glowing colour, translucency and freedom from fractures give carnelian its value — both as polished cabochons and beads and as natural nodules showing rich colour.
About Carnelian
Carnelian is classified as a silicate mineral in the quartz group (chalcedony varieties) and has the chemical formula SiO2 (Fe-bearing chalcedony variety). It crystallizes in the trigonal system and holds a steady position among silicate species.
Identification & care
Carnelian typically forms massive, nodular, veins. Its color range is broad, including orange-red, brownish-red, red, and pale orange. The luster is waxy, the streak is white, and specimens are typically translucent. The fracture is conchoidal, which is one of its key identifying features.
Collector context
Collector notes
Among ornamental materials, Carnelian has a recognized place in collections.
Frequently asked questions
What is Carnelian?
Carnelian is a silicate mineral recognized among collectors for its crystal form and distribution.
What is the chemical formula of Carnelian?
The chemical formula of Carnelian is SiO2 (Fe-bearing chalcedony variety).
What crystal system does Carnelian belong to?
Carnelian crystallises in the Trigonal crystal system.