Black Jet
Jet (Lignite variety) · Organic Gem
Crystal System
Amorphous (Non-crystalline)
Mineral Group
Organic Mineraloid
Chemical Formula
C (Amorphous carbon with complex hydrocarbon compounds)
Formation Process
Sedimentary organic fossilization resulting from the carbonization of fossilized drift wood from specific extinct tree species under high pressure
About This Crystal
The specimen consists of heavily polished, rounded, dark black beads carved into smooth cubic or barrel-like shapes with a deep, velvety black luster and opaque transparency.
Physical Characteristics
Color is deep jet black; streak is brownish-black; cleavage is none; fracture is conchoidal; specific gravity is approximately 1.30 to 1.35; tenacity is brittle; entirely non-magnetic and non-fluorescent.
Optical Properties
Isotropic (singly refractive) due to its amorphous nature; refractive index is approximately 1.66; displays a deep vitreous to resinous luster when polished.
Hardness & Durability
Origin Region
Whitby (UK), Spain, USA, France, Germany, and Russia; formed in marine or freshwater shale environments
Hardness & Durability
Mohs hardness is 2.5 to 4.0; very low durability and toughness compared to standard gemstones; scratches easily and sensitive to extreme heat, alcohol, and harsh chemicals.
Care & Maintenance
Clean gently with a soft, damp cloth and mild soap; avoid ultrasonic cleaners, steam, alcohol, perfumes, and prolonged direct sunlight; store separately in a soft pouch.
Rarity & Value
Uncommon as genuine antique or high-grade gem material; value is determined by uniformity, high polish without cracks, and historical provenance; price range is moderate.
Special Characteristics
When rubbed with a cloth, jet can acquire a static electrical charge capable of attracting light particles, a property known since antiquity.
Lore & History
Historically used extensively in Victorian mourning jewelry following the death of Prince Albert; traditionally associated with deep grief protection, grounding, and absorbing negative energy in metaphysical practices.