Tektite
Tektite (Indochinite variety) · Meteoritic Material / Impact Glass
Crystal System
Amorphous (Non-crystalline material)
Mineral Group
Natural Glass (Not a mineral in the strict sense)
Chemical Formula
SiO2 (approx. 75%) + Al2O3, FeO, MgO, CaO, Na2O, K2O
Formation Process
Extraterrestrial impact involving rapid melting of terrestrial silica-rich soil followed by atmospheric solidification
About This Crystal
A dark, opaque, glass-like specimen with a pitted, 'dimpled' surface texture known as sculpturing. It displays a sub-vitreous to dull luster and a blackish-brown to charcoal color.
Physical Characteristics
Color: Black/Deep Brown; Streak: White; Cleavage: None; Fracture: Conchoidal; Density: 2.3–2.5; Fluorescence: None; Tenacity: Brittle.
Optical Properties
Isotropic (singly refractive) with a refractive index of approximately 1.48–1.51. Non-pleochroic and lacks birefringence.
Hardness & Durability
Origin Region
Indochina strewn field (Thailand, Vietnam, Cambodia, Laos); formed by meteorite impact
Hardness & Durability
Mohs hardness of 5.5 to 6.5. Toughness is poor due to its brittle, glassy nature; similar to obsidian.
Care & Maintenance
Clean with warm soapy water and a soft cloth. Avoid ultrasonic cleaners and sudden temperature changes to prevent cracking.
Rarity & Value
Relatively common in strewn fields. Value is determined by size, aerodynamics (buttons, dumbbells), and surface texture. Usually $1-$10 per gram.
Special Characteristics
Features aerodynamically shaped pits and grooves (regmaglypts) caused by high-velocity flight through the atmosphere.
Lore & History
Traditionally believed by many cultures to be 'seed of the stars.' Used as talismans for grounding and protection against psychic debris.