mineraloid / impact glass

Tektite (Indochinite)

Tektite (High-silica natural glass)

Hardness: 5.5-6.5 on Mohs scale; Color: Black, dark brown (usually translucent on thin edges); Luster: Vitreous to dull; Crystal structure: Amorphous (glassy); Cleavage: Conchoidal fracture; Specific gravity: 2.3-2.5

Hardness: 5
Color: Black, dark brown (usually translucent on thin edges)
Luster: Vitreous to dull

Identified March 11, 2026More mineraloid / impact glass →

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Physical properties

Formation & geological history

Formed from terrestrial debris ejected into the atmosphere during a meteorite impact, which cooled rapidly back to Earth. Indochinites are associated with the Australasian strewn field, formed approximately 780,000 years ago.

Uses & applications

Primarily used for gemstone jewelry (faceted or cabochon), metaphysical collecting, and scientific research into meteorite impact events.

Geological facts

Tektites contain almost no water, unlike volcanic glass (obsidian). The pitted surface is caused by aerodynamic ablation as the molten material re-entered the atmosphere at high speeds.

Field identification & locations

Identify by its pitted, scalloped surface (regmaglypts), lack of crystals, and dark black color that may appear olive green or brown when held to a strong light. Found mostly in Southeast Asia (Thailand, Vietnam, Cambodia).

Other mineraloid / impact glass specimens

See all

Tektite (specifically Indochinite)

Tektite (Natural silica glass)

Mineraloid (Impact glass)

Tektite (Indochinite)

Tektite - High-silica amorphous glass (SiO2 + Al2O3)

mineraloid

Tektite (Indochinite)

Tektite (High-silica impact glass)

mineraloid

Sea Glass (often mistaken for Gemstones)

Amorphous Silica (SiO2) with trace additives

mineraloid

Moldavite

Silica glass with small amounts of aluminum, iron, and other elements

Mineraloid / Tektite

Tektite (likely Australite)

Tektite (no specific chemical formula as it's a natural glass of variable composition, mostly SiO2, Al2O3, FeO, MgO, CaO, K2O, Na2O, TiO2)

Mineral (specifically a mineraloid)