igneous

Tektite (Indochinite)

Tektite (High-silica natural glass)

Hardness: 5.5-6.5; Color: Black, dark brown to olive green; Luster: Vitreous to dull; Structure: Amorphous (non-crystalline glass); Cleavage: None, conchoidal fracture; Specific gravity: 2.3-2.5

Hardness: 5
Color: Black, dark brown to olive green
Luster: Vitreous to dull

Identified January 12, 2026More igneous →

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Physical properties

Hardness: 5.5-6.5; Color: Black, dark brown to olive green; Luster: Vitreous to dull; Structure: Amorphous (non-crystalline glass); Cleavage: None, conchoidal fracture; Specific gravity: 2.3-2.5

Formation & geological history

Formed from terrestrial debris ejected into the atmosphere during a high-energy meteorite impact. The molten material cooled rapidly in flight to form glass. This specimen likely belongs to the Australasian strewn field, formed approximately 790,000 years ago.

Uses & applications

Primarily used by collectors, as decorative gemstone cabochons, and in metaphysical jewelry.

Geological facts

Tektites are unique because they are almost entirely dehydrated, containing significantly less water than volcanic glasses like obsidian. They are often found thousands of miles away from the original impact site.

Field identification & locations

Identify by its pitted, aerodynamically sculpted surface (regmaglypts) and conchoidal fracture. Found in specific 'strewn fields' in areas like Thailand, Vietnam, and Australia. Collectors should look for the characteristic dimpled texture which distinguishes it from terrestrial slag or obsidian.

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