Moldavite
Tektite (Natural Glass) · Collector Mineral / Impactite Gemstone
Crystal System
Amorphous (Non-crystalline glass)
Mineral Group
Silicate Glass (Tektite group)
Chemical Formula
SiO2 + Al2O3, FeO, MgO, CaO, Na2O, K2O (Lechatelierite-rich silica glass with extraterrestrial impact origin)
Formation Process
Impactite formation; created approximately 15 million years ago when a massive meteorite struck the Earth, melting terrestrial surface rocks and propelling the silica-rich vapor and melt high into the atmosphere before solidifying as it fell back to Earth.
About This Crystal
This is a substantial specimen of deep olive-green to forest-green tektite glass. It features a characteristic rough, textured surface with deep pits, wrinkles, and flow lines (sculpting caused by natural acid etching in the soil). The transparency ranges from translucent to opaque due to its thickness and internal lechatelierite gas bubbles and swirls.
Physical Characteristics
Color is deep bottle green to brownish-green. Streak is white (none for glass). Luster is vitreous to greasy. Fracture is distinctly conchoidal. Specific gravity ranges from 2.32 to 2.38. Tenacity is brittle. It has no cleavage plane due to its amorphous, glassy structure. It is non-magnetic and does not react to UV light.
Optical Properties
Singly refractive (isotropic glass) with a refractive index of approximately 1.48 to 1.51. It does not exhibit pleochroism or birefringence. Internal features often show swirling flow lines, elongated lechatelierite inclusions, and spherical or distorted gas bubbles.
Hardness & Durability
Origin Region
Bohemia and Moravia, Czech Republic (Moldau River valley); formed by a meteorite impact at the Ries crater in southern Germany.
Hardness & Durability
Mohs hardness is 5.5 to 6.5, making it relatively durable for jewelry if set protectively, though its brittle nature and conchoidal fracture make it susceptible to chipping from sharp impacts.
Care & Maintenance
Clean with warm soapy water and a soft brush. Avoid ultrasonic cleaners, harsh chemicals, or sudden thermal shock. Store separately in a soft pouch to prevent scratching softer stones or being scratched by quartz.
Rarity & Value
Rare and highly sought after by collectors and spiritual practitioners. Value is determined by weight (grams), sculptural quality, texture, color intensity, and provenance. Prices range from tens to hundreds of dollars per gram for authentic specimens.
Special Characteristics
Contains lechatelierite inclusions (pure silica glass particles) and microscopic aerodynamic gas bubbles trapped during its high-speed atmospheric flight following the meteorite impact.
Lore & History
Moldavite has been used as a talisman and adornment since the Stone Age, with specimens found near Paleolithic sites. In modern crystal healing, it is revered as a powerful stone of spiritual transformation, rapid personal evolution, and awakening, linked primarily to the heart and third-eye chakras. These are traditional and metaphysical beliefs, not scientifically validated properties.