
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 More mineraloid →
Identify your own rocks.
Get a report just like this from any photo, free.
Physical properties
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
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.
More like this
Other mineraloid specimens
Amber
Succinite (Organic Mineraloid)
mineral
Fulgurite
Fulgurite (Lechatelierite)
metamorphic
Black Obsidian
Volcanic Glass (SiO2 + impurities)
Igneous
Obsidian
Volcanic glass
igneous
Limonite (Ironstone)
Limonite (mixture of hydrated iron oxides, primarily Goethite α-FeO(OH))
mineral
Obsidian
Volcanic glass (SiO2 - Silicon Dioxide with impurities)
igneous