igneous

Tektite (Indochinite)

Tektite (Amorphous silica-rich impact glass)

Hardness: 5.5-6.5 (Mohs scale); Color: Black (translucent brown on thin edges); Luster: Vitreous to dull; Structure: Amorphous (non-crystalline glass); Specific Gravity: 2.3-2.5

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

Identified March 21, 2026More igneous →

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Physical properties

Hardness: 5.5-6.5 (Mohs scale); Color: Black (translucent brown on thin edges); Luster: Vitreous to dull; Structure: Amorphous (non-crystalline glass); Specific Gravity: 2.3-2.5

Formation & geological history

Formed from terrestrial debris ejected into the atmosphere during a meteorite impact, which cooled rapidly while falling back to Earth. This specific Indo-Australian strewn field event occurred approximately 790,000 years ago.

Uses & applications

Used primarily by gemstone collectors, in jewelry as beads or pendants, and in some metaphysical practices. Historically used for making tools by ancient cultures.

Geological facts

Tektites contain almost no water (averaging 0.005%), which distinguishes them from volcanic obsidian. The pitted surface features, called 'sculpturing,' are caused by chemical etching or aerodynamic stresses during atmospheric reentry.

Field identification & locations

Identify in the field by its distinctive pitted 'skin,' aerodynamic shape, and lack of internal crystals. Commonly found in Southeast Asia, Australia, and parts of China within the Australasian strewn field.

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