Moldavite Identification Guide
A field guide to identifying genuine Moldavite, a forest-green tektite, by its natural etched surface, bubbles, schlieren, and low density.
Read the full Moldavite encyclopedia entry →
What Moldavite Looks Like
Moldavite is a natural glass (a tektite) formed about 15 million years ago by a meteorite impact (the Ries crater, Germany). It is a deep to pale forest-green, translucent glass with a distinctive wrinkled, etched, and pitted natural surface.
- Color: Olive to forest green, sometimes brownish-green; translucent.
- Luster: Vitreous (glassy).
- Transparency: Translucent.
- Habit/form: Irregular natural blobs, drops, and fragments with a sculpted, etched ("weathered") surface texture; amorphous glass.
Step-by-Step Field ID Checklist
- Inspect the surface texture: Genuine moldavite has a natural, deeply etched, wrinkled, lacy "weathering" sculpture from being in soil. This is the single best field clue.
- Backlight it: Translucent forest green with internal swirls (schlieren) and round to elongated gas bubbles.
- Look for bubbles and schlieren under a loupe: Natural moldavite shows irregular, often elongated bubbles and flow lines; molded fakes show perfectly round bubbles or none.
- Check the green tone: Natural moldavite green is mossy/bottle-green; overly bright "emerald" green often signals man-made glass.
- Confirm hardness and density (below).
Key Diagnostic Tests
- Mohs hardness: ~5.5–7 (about 5.5–6 typical for tektite glass).
- Streak: White.
- Fracture: Conchoidal with sharp edges.
- Density: ~2.32–2.38 g/cm3 — quite light, a useful check.
- Acid: Inert to dilute HCl; resists ordinary acids (true moldavite is not easily etched by household acid).
- Magnetism: None.
Common Look-Alikes and How to Tell Them Apart
- Manufactured green glass (the main fake): Look for mold seams, perfectly round bubbles, an artificially smooth or uniformly "pitted" (acid-etched) surface, and an unnaturally vivid green. Real moldavite's etch pattern is irregular and three-dimensional.
- Green obsidian: Volcanic (not impact) glass; usually more uniformly colored, lacks the characteristic moldavite weathering sculpture, and often man-made when bright green.
- Other tektites: Most tektites are brown/black; moldavite's green color and central-European origin are distinctive.
- Peridot/green gems: Crystalline, harder, doubly refractive — not glass.
- Bottle-glass tumbles: Frosted, rounded, may show mold marks.
Where It Is Found
Moldavite is found only in a strewn field in the Czech Republic — chiefly Bohemia (Besednice, around the Vltava/Moldau River, from which it is named) and Moravia. Because the source is limited, counterfeits are extremely common.
Frequently asked questions
How can you tell if Moldavite is real?
Genuine moldavite has a natural, irregular etched and wrinkled surface, translucent forest-green color, internal schlieren (flow swirls) and often elongated gas bubbles, hardness ~5.5–6, and a light density of ~2.32–2.38. Mold seams, perfectly round bubbles, and an overly vivid green indicate fake glass.
What does real Moldavite look like?
It is a translucent, mossy forest-green natural glass with a deeply sculpted, wrinkled, etched surface and internal swirls and bubbles, occurring as irregular blobs and fragments rather than smooth shapes.
Moldavite vs green glass fakes — how do you tell them apart?
Fakes are usually molded glass with seams, perfectly round bubbles, smooth or uniformly etched surfaces, and unnaturally bright green. Real moldavite shows irregular natural weathering sculpture, elongated bubbles, and a softer bottle-green color.
Is Moldavite an obsidian or a tektite?
Moldavite is a tektite — natural glass formed by a meteorite impact, not volcanic obsidian. It comes from the Czech Republic and is associated with the Ries impact crater.
Moldavite identified by the community
Recent Moldavite specimens identified with Rock Identifier.
