Anthropogenic specimen (Man-made material)

Sea Glass (Kelly Green)

Amorphous Silica (Silicon Dioxide with Iron/Chromium additives)

Hardness: 5.5-6.5 (Mohs scale); Color: Kelly Green; Luster: Frosted/Vitreous; Crystal Structure: Amorphous (non-crystalline); Cleavage: Conchoidal fracture; Specific gravity: 2.4-2.5

Hardness: 5
Color: Kelly Green
Luster: Frosted/Vitreous

Identified March 21, 2026More anthropogenic specimen (man-made material) →

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Physical properties

Hardness: 5.5-6.5 (Mohs scale); Color: Kelly Green; Luster: Frosted/Vitreous; Crystal Structure: Amorphous (non-crystalline); Cleavage: Conchoidal fracture; Specific gravity: 2.4-2.5

Formation & geological history

Formed from discarded glass bottles or jars. Over decades (typically 20-50 years), the glass is physically weathered by salt water and tumbled by sand and rocks in the ocean or large lakes, resulting in smoothed edges and a frosted surface texture.

Uses & applications

Used primarily in jewelry making (pendants, rings), decorative mosaics, terrariums, and as a popular collectible item for beachcombers.

Geological facts

The frosted appearance is caused by 'hydration,' a chemical process where soda and lime leach out of the surface of the glass leaving tiny pits. This specific green often originates from vintage 7-Up, Heineken, or Sprite bottles.

Field identification & locations

Identify by looking for rounded, non-sharp edges and a characteristic 'frosted' or pitted surface. Found on coastal shorelines, particularly after storms. Collectors look for pieces with no remaining shiny surfaces.

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