Anthropogenic (Man-made material processed by nature)

Sea Glass (Turquoise/Aqua)

Amorphous Silica (SiO2) with transition metal dopants

Hardness: 5.5-7 (Mohs scale); Color: Turquoise/Aqua/Teal; Luster: Frosted, matte, or satiny; Crystal Structure: Amorphous (non-crystalline); Specific Gravity: 2.4-2.8; Cleavage: Conchoidal (fractures like a shell)

Hardness: 5
Color: Turquoise/Aqua/Teal
Luster: Frosted, matte, or satiny

Identified March 9, 2026More anthropogenic (man-made material processed by nature) →

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Physical properties

Formation & geological history

Formed from discarded glass waste (bottles, jars, or tableware) that has been tumbled by the ocean's waves and sand for 20 to 100+ years. The frosted appearance is caused by a chemical process known as hydration, where soda and lime leach from the glass surface.

Uses & applications

Broadly used in jewelry (wire-wrap or drilled pendants), decorative mosaics, home decor, and as a popular focus for hobbyist collectors.

Geological facts

Turquoise/Teal sea glass is often derived from vintage seltzer bottles, high-end perfume bottles, or decorative glassware from the mid-20th century. It is consider a 'rare' to 'semi-rare' find compared to green, brown, or clear glass.

Field identification & locations

Identify in the field by searching along shingle beaches or rocky shorelines. Look for 'C' shaped hydration marks (pitting) on the surface, which distinguishes genuine sea glass from craft-store 'tumbled' glass. Finding rounded edges with no sharp points indicates a well-aged specimen.

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Sea Glass (Teal/Turquoise)

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