Anthropogenic (Man-made product subject to geological processes)
Sea Glass (White/Clear)
Amorphous Silica (Alkali-Lime-Silica Glass), SiO2 + Na2O + CaO
Hardness: 5.5-7 (Mohs); Color: Frosty white or translucent; Luster: Matte to frosty; Crystal Structure: Amorphous (non-crystalline); Cleavage: None (conchoidal fracture when broken); Specific Gravity: 2.4-2.8
- Hardness
- 5
- Color
- Frosty white or translucent
- Luster
- Matte to frosty
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Physical properties
Hardness: 5.5-7 (Mohs); Color: Frosty white or translucent; Luster: Matte to frosty; Crystal Structure: Amorphous (non-crystalline); Cleavage: None (conchoidal fracture when broken); Specific Gravity: 2.4-2.8
Formation & geological history
Formation process involves man-made glass entering marine or freshwater environments. Over 20-50+ years, the movement of water and abrasive contact with sand/rocks creates weathered edges and a 'frosted' surface via hydration and pH-driven etching.
Uses & applications
Used primarily in jewelry making, mosaic arts, home decor, and as a popular focus for beachcombing hobbyists.
Geological facts
Genuine sea glass has a 'frosty' surface caused by the leaching of soda and lime, leaving tiny 'C' shaped hydration marks. True sea glass is becoming rarer as the world moves from glass bottles to plastic containers.
Field identification & locations
Identify in the field by looking for rounded edges (no sharp points) and a smooth, frosted texture that feels slightly waxy when dry. Common on rocky beaches or shorelines near old coastal dump sites or high ship traffic.
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