Mineral-like (Natural Glass)

Tektite (Indochinite)

Tektite (Lechatelierite-rich silica glass)

Hardness: 5.5-6.5 on Mohs scale; Color: Black, dark green, or brownish-black; Luster: Vitreous (glassy); Crystal Structure: Amorphous (non-crystalline glass); Specific Gravity: 2.3-2.5; Cleavage: None (conchoidal fracture).

Hardness: 5
Color: Black, dark green, or brownish-black
Luster: Vitreous (glassy)

Identified April 26, 2026More mineral-like (natural glass) →

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Physical properties

Formation & geological history

Formed from terrestrial debris ejected during meteorite impacts. The extreme heat of the impact melts surface rocks, which are flung into the atmosphere and solidify into glass as they fall back to Earth. This specimen appears to be an Indochinite, formed approximately 700,000 to 800,000 years ago.

Uses & applications

Primarily used for gemstone jewelry, metaphysical collecting, and as scientific specimens in geology and astronomy collections.

Geological facts

Tektites contain almost no water, which distinguishes them from volcanic glasses like obsidian. They are part of a 'strewn field'—a large geographic area where these specimens are found thousands of miles from the original impact crater.

Field identification & locations

Identify by its pitted or 'sculpted' surface (aerodynamic skin), glassy interior, and lack of internal crystals. Indochinites are commonly found across Southeast Asia, Australia, and parts of China.

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