Moldavite
Last updated: April 2026
Tektite — natural glass formed ~14.8 million years ago by a meteorite impact in the Ries crater (Germany), with ejected melt landing in what is now the Czech Republic. The only gem-quality tektite. Heavily faked with manufactured green glass; genuine moldavite has lechatelierite inclusions and sculptured surface texture.
Moldavite has a specific gravity of 2.35 and a refractive index of 1.480–1.510, with a Mohs hardness of 6. It is singly refractive.
Physical & Optical Properties
Key Differentiators
- Unique sculptured/etched exterior surface with flow ridges, pitting, and corrosion features
- Lechatelierite inclusions — wispy pure SiO₂ glass threads unique to tektites, absent in man-made glass
- Low SG 2.32–2.38 — lighter than most glass fakes (~2.40+) and most other green stones
- Found ONLY in Bohemia/Moravia (Czech Republic) — any 'moldavite' from elsewhere is fake
- Flow structures (schlieren) and gas bubbles under loupe — no crystalline inclusions possible
Common Simulants
- Manufactured Green Glass: Green glass fakes lack lechatelierite inclusions. Glass fakes typically have higher SG (2.40+), may show mold seams, and lack the organic sculptured surface corrosion of genuine moldavite. Look for lechatelierite under 20–40× magnification — its presence indicates genuine moldavite.
- Green Tourmaline: Tourmaline is crystalline (doubly refractive), RI 1.624–1.644, much higher than moldavite glass (1.48–1.51). SG 3.06. Not isotropic.
- Green Sapphire: Sapphire RI 1.762–1.770 is far higher than moldavite. SG 3.99–4.05. Not comparable on any standard test.
Price Context
Price context is approximate. Loupewise is not an appraisal tool. Results are indicators, not certified valuations.
Measurement Guides
Identifying a moldavite? Loupewise walks through these tests in order — RI, SG, fluorescence, and more.
Try Loupewise Free →Studying for the GIA, FGA, or FEEG practical? Moldavite is one of the 130 species in Loupewise’s drill and exam pool — practice identifying it from its measured properties under timed exam conditions.
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