gemstone

Tumbled moldavite specimens

Moldavite (natural tektite; silica-rich impact glass), approximately SiO₂ 75–80%

AI-generated identification · may be incorrect

Hardness about 5.5–6.5 Mohs; translucent moss-green to olive-green, vitreous luster, amorphous glass with no cleavage. Natural moldavite commonly has etched, sculpted surface texture, though these pieces appear polished or partly polished.

Identified September 22, 2026More gemstone →

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Physical properties

Formation & geological history

Formed roughly 14.7 million years ago when the Ries impact in Bavaria, Germany, melted terrestrial rock and ejected glass that fell across Central Europe. Principal sources are southern Bohemia, Moravia, and nearby regions of the Czech Republic.

Uses & applications

Used as a collectible tektite and gemstone in pendants, cabochons, and carved jewelry; it has little industrial use. Genuine high-quality material is prized for its color, transparency, and natural sculpturing.

Geological facts

Moldavite is among the rarest tektites and is often imitated with green bottle glass. Its unusual green color and extraterrestrial impact origin make it highly sought after.

Field identification & locations

Identify genuine pieces by natural pitted or wrinkled texture, internal bubbles and flow structures, moderate glass hardness, and a lack of perfectly uniform color; laboratory testing is advisable because the image shows polished pieces. Common localities include Besednice, Chlum, and Slavče in Czechia.