mineraloid

Glass

Amorphous Silicon Dioxide (SiO2)

Hardness: 5.5–6.0 (Mohs scale); Color: Transparent to translucent, often artificially colored; Luster: Vitreous; Crystal Structure: Amorphous (non-crystalline); Cleavage: None (conchoidal fracture); Specific Gravity: 2.4–2.8

Hardness: 5
Color: Transparent to translucent, often artificially colored
Luster: Vitreous

Identified January 16, 2026More mineraloid →

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Physical properties

Formation & geological history

Formed by the rapid cooling of molten silica-rich materials, preventing the formation of a crystalline lattice. While volcanic glass (obsidian) is igneous, this specimen is a man-made silicate material created through industrial melting processes.

Uses & applications

Primary material for containers, windows, laboratory equipment, and decorative items. In a jewelry context, it is used for beads and imitation gemstones. In industry, it is essential for fiber optics and insulation.

Geological facts

Glass is considered a 'mineraloid' rather than a mineral because it lacks an ordered internal atomic structure. It has been manufactured by humans since at least 3500 BCE in Mesopotamia.

Field identification & locations

Identify in the field by its characteristic conchoidal (shell-like) fracture patterns and lack of crystal faces. In this specific specimen, it is identified by its uniform transparency and molded shape forming a 'Gran Duque d'Alba' bottle.