Comparison · Materials vs Tektites
Glass vs Moldavite
Glass and Moldavite are easy to confuse. Both sit near Mohs 5.5, so a scratch test alone will not separate them. Lean on luster, streak and heft instead. Below is a side-by-side comparison of their properties and the quick tests that separate them.
Key differences between Glass and Moldavite
- Both sit near Mohs 5.5, so a scratch test alone will not separate them. Lean on luster, streak and heft instead.
- Streak color differs: Glass leaves a white to colorless streak on unglazed porcelain, Moldavite leaves white.
- They overlap in green, but Glass also comes in brown, clear, and blue.
Glass vs Moldavite properties
| Property | Glass | Moldavite |
|---|---|---|
| Type | Materials | Tektites |
| Mohs hardness | 5.5 | 5.5 |
| Luster | vitreous | vitreous |
| Streak | White to colorless | White |
| Transparency | translucent | translucent |
| Specific gravity | 2.5 | 2.4 |
| Crystal system | amorphous | amorphous |
| Common colors | Green, Brown, Clear, Blue, White, Frosted | Forest Green, Olive Green |
| Rarity | common | rare |
| Typical specimen value | $1–$40+ | $50–$2000+ |
Which is more valuable?
Moldavite is usually the more valuable of the two: a typical collector specimen runs about $200 against $5 for Glass, and premium Moldavite can reach $2000 or more.
About Glass
Glass is a man-made amorphous material. Surf-tumbled sea glass and weathered bottle shards are among the most common glassy finds mistaken for natural minerals.
About Moldavite
Moldavite is a green tektite formed by a meteorite impact about 15 million years ago. Found only in the Czech Republic, it's prized by collectors and crystal enthusiasts.
Glass vs Moldavite FAQ
Is Glass the same as Moldavite?
No. Glass is a material while Moldavite is a tektite. Both sit near Mohs 5.5, so a scratch test alone will not separate them. Lean on luster, streak and heft instead.
How can you tell Glass from Moldavite?
Both sit near Mohs 5.5, so a scratch test alone will not separate them. Lean on luster, streak and heft instead. Streak color differs: Glass leaves a white to colorless streak on unglazed porcelain, Moldavite leaves white. They overlap in green, but Glass also comes in brown, clear, and blue.
Which is harder, Glass or Moldavite?
They are about equally hard, both near Mohs 5.5.
Which is more valuable, Glass or Moldavite?
Moldavite is usually the more valuable of the two: a typical collector specimen runs about $200 against $5 for Glass, and premium Moldavite can reach $2000 or more.
