Rock Identifier
Moldavite (SiO2 (+ Al2O3, FeO, K2O) - Natural Tektite Glass) — gemstone
gemstone

Moldavite

SiO2 (+ Al2O3, FeO, K2O) - Natural Tektite Glass

Hardness: 5.5 - 6.5 on Mohs scale; Color: Forest green to olive green; Luster: Vitreous (glassy); Crystal Structure: Amorphous (non-crystalline glass); Cleavage: None (conchoidal fracture); Specific Gravity: 2.32 - 2.40

Hardness
5
Color
Forest green to olive green
Luster
Vitreous (glassy)
Identified More gemstone
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Physical properties

Hardness: 5.5 - 6.5 on Mohs scale; Color: Forest green to olive green; Luster: Vitreous (glassy); Crystal Structure: Amorphous (non-crystalline glass); Cleavage: None (conchoidal fracture); Specific Gravity: 2.32 - 2.40

Formation & geological history

Formed approximately 15 million years ago by a meteorite impact in Southern Germany (Nördlinger Ries crater). The intense heat and pressure melted surrounding terrestrial rock and ejected it high into the atmosphere, which cooled mid-air and settled primarily in Bohemia and Moravia, Czech Republic.

Uses & applications

Highly sought after by mineral collectors, used in fine jewelry (faceted gems, wire-wrapped pendants), and popular in metaphysical/crystal healing communities.

Geological facts

Moldavite is one of the rarest tektites in the world due to its single known locality of origin. Specimens often exhibit distinctive sculpted, pitted surfaces (sculptuming) created by atmospheric erosion during entry and subsequent soil interaction.

Field identification & locations

Look for the characteristic bottle-green to olive-green color, distinct pitted and grooved surface texture, and internal gas bubbles (lechatelierite inclusions) under magnification. The reported location in Minas Gerais, Brazil (20.1°S, 42.0°W) is known for emerald, tourmaline, and alexandrite, but Moldavite is native only to the Czech Republic, meaning this specimen was brought there via trade or collection.