gemstone
Jet
Hydrocarbon-rich fossilized wood
AI-generated identification · may be incorrectHardness of 2.5 to 4 on the Mohs scale, deep black or dark brown color, velvety to vitreous luster, amorphous crystal structure with conchoidal fracture, and a specific gravity of 1.3 to 1.4.
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Physical properties
Hardness of 2.5 to 4 on the Mohs scale, deep black or dark brown color, velvety to vitreous luster, amorphous crystal structure with conchoidal fracture, and a specific gravity of 1.3 to 1.4.
Formation & geological history
Formed from the fossilization of wood from specific extinct trees under extreme pressure in stagnant, oxygen-deficient aquatic environments, typically dating from the Jurassic to Tertiary periods.
Uses & applications
Historically used for mourning jewelry, carved decorative ornaments, and rosaries due to its ability to take a high polish and lightweight feel.
Geological facts
Jet has been prized since the Neolithic period and was famously mass-produced for Victorian mourning jewelry following the death of Prince Albert.
Field identification & locations
Identified by its extremely light weight, warm touch compared to cold mineral stones, and the brownish streak it leaves on unglazed porcelain. Commonly sourced from Yorkshire in England and Asturias in Spain.
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