Cobalt Blue Sea Glass
Manufactured glass
Markings and exact colorations may vary.
Deep blue glass from old medicine and poison bottles. The find that stops a walk.
- Typical size
- Half an inch to 1.5 inches
- How often it turns up
- Rare
- Collecting
- Check local rules
- Handling
- Safe to handle
Loose glass may be collectable where permitted; follow park and protected-area rules. Do not take from archaeological sites or wreck contexts. Dispose of sharp modern litter safely.
No hazard once fully frosted.
How to tell it apart
- Deep saturated blue
- Uniformly frosted surface
- Often thicker than green glass
Found one?
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Commonly confused with
Green Sea GlassManufactured glass
Both must be fully frosted to count as finished sea glass. Cobalt is far rarer and usually thicker.
More sea glass in the field guide
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