Tektite — Properties, Meaning, and Uses

Tektite is a natural glass formed by the impact of large meteorites that vaporize and fuse terrestrial material, which then falls back to Earth solidified into aerodynamic shapes. With a hardness of 5.5–7 Mohs and a black or dark brown vitreous appearance, it is distributed in specific strewn fields around the world. Moldavite—its most well-known green variant—has its own guide in this encyclopedia. Property Value Mineralogical Name Tektite (natural impact glass) Composition SiO₂ (65–82%) + Al₂O₃, FeO, MgO, CaO, TiO₂ Mineral Group Natural Glasses (amorphous) Crystal System Amorphous (no crystalline structure) Hardness (Mohs) 5.5–7 (depending on type) Density 2.3–2.5 g/cm³ Luster Vitreous Fracture Conchoidal (characteristic of glass) Color Black, dark brown, olive green (moldavite), yellowish green Streak White to colorless Diaphaneity Opaque to translucent in thin sheets Strewn Fields Australia, Southeast Asia, Eastern North America, West Africa, Central Europe (moldavite) What is Tektite? Tektite is a natural glass of cosmic origin formed when a large meteorite impacts Earth with enough energy to vaporize and melt the superficial terrestrial material. The molten material is ejected into the atmosphere or near-space; during its return flight, the liquid droplets cool and solidify, acquiring aerodynamic shapes—buttons, dumbbells, drops, spheres—before scattering over vast geographical areas called strewn fields. Tektites are not meteorites: their composition reflects terrestrial crust melted by impact (rich in silica, aluminum, iron, and magnesium), not the projectile material itself. However, they may contain traces of the meteorite in the form of nickel-iron inclusions or metallic microspheres. Moldavite—a deep green glass formed 14.7 million years ago by the Nördlingen impact (Germany)—is the most commercialized variant and has its own guide in this encyclopedia. The term "tektite" was coined in 1900 by geologist Eduard Suess, derived from the Greek tēktos (molten). Since then, more than a hundred thousand specimens from various strewn fields have been geochemically characterized. Physical and Chemical Properties Composition and Structure Tektites are amorphous siliceous glasses with no crystalline structure. The composition varies by strewn field: Australites and Indochinites have 65–75% SiO₂; Moldavites, up to 80–82% SiO₂. Al₂O₃ content ranges from 10 to 15%; iron oxides (FeO + Fe₂O₃) are between 4 and 8%. This composition is similar to that of crustal rocks like greywackes or shales, consistent with the terrestrial origin of the material. The absence of structural water—tektites contain less than 0.02% H₂O—distinguishes them from volcanic glasses like obsidian, which can have up to 0.3% or more. This difference is diagnostic for identification. Hardness and Durability Hardness varies between 5.5 and 7 Mohs depending on the strewn field and silica content. More siliceous moldavites are harder. Conchoidal fracture is perfectly developed in all types, creating sharp edges when broken—a characteristic of glass. They do not exhibit cleavage. They are relatively fragile against direct impacts despite acceptable hardness. Optical Properties The refractive index ranges from 1.46 to 1.54 depending on the type. They are isotropic (amorphous), which differentiates them from quartz and other crystalline silicates under a polarized microscope. In thin sections of 1–2 mm, they are translucent to transparent in brown, greenish, or yellowish tones; in bulk, they are opaque or nearly opaque. Surface and Morphology The surface of tektites is often marked by chemical corrosion during their geological exposure: grooves, pits, and rough dissolution textures are common. Australites have an aerodynamic button shape formed during atmospheric re-entry. Asian tektites (Indochinites) show spherical, dumbbell, or teardrop shapes. Moldavite has the roughest and most corroded texture of all types. Tektite Types and Strewn Fields Type Age (Ma) Strewn Field Color / Typical Shape Australites 0.79 Australia, Antarctica Black, aerodynamic button Indochinites 0.79 Southeast Asia, Southern China Black-brown, spherical, dumbbell Georgiaites / Bediasites 34–35 Georgia and Texas (USA) Green-yellow, irregular Ivory Coast Tektites 1.07 Ivory Coast, Ghana Black, irregular Moldavite 14.7 Bohemia, Moravia, Lusatia Bottle green, highly corroded Australites and Indochinites belong to the same impact event (Australasian field, 0.79 Ma), the largest and most recent documented strewn field. The causative crater has not been certainly identified; current geological candidates point to a region in Southeast Asia or the Indian Ocean. Where are Tektites Found? Australia produces the most distinctive Australites, with the unmistakable aerodynamic button shape formed by high-speed atmospheric re-entry. The most accessible deposits are in Southern Australia (Victoria, South Australia). Southeast Asia (Thailand, Vietnam, Cambodia, Laos, Philippines, Indonesia) is the region with the greatest abundance of Indochinites. In Southern China (Guangdong, Hainan), the so-called "Chinese tektites" are found. The largest specimens—up to several hundred grams—are obtained from lateritic deposits in Vietnam and Thailand. In North America, Texas Bediasites are rare and valued by collectors for their greenish-yellow color. In Ivory Coast and Ghana, 1.07 Ma Ivoirites are found, in smaller quantities and with less commercial distribution. Uses of Tektite In Jewelry and Lapidary Larger, regularly shaped tektites are cut into cabochons for pendants and earrings. Natural button-shaped Australites are mounted unset, utilizing their characteristic aerodynamic morphology as a visual element. Moldavite, due to its intense green color and rarity, is the most sought-after in collector's jewelry. A tektite cabochon is an option for unique pieces: each specimen is unrepeatable in shape and texture. For wire wrapping and artisan setting, natural rough pieces are common in our rough minerals section. In Scientific Collecting Tektites are of great interest to meteorite and planetary geology collectors due to their cosmic-terrestrial origin. Complete specimens with intact aerodynamic morphology (button Australites) or with well-preserved characteristic chemical corrosion are the most valued. Weight, shape, exact provenance of the field, and absence of repairs are the determining factors of price in serious collecting. Tektite in Cultural and Spiritual Tradition The properties described in this section belong to the cultural tradition of crystal healing and do not constitute medical advice. History and Ancestral Uses In Indochina, tektites were found at prehistoric ritual sites more than 700,000 years ago—associated with stone tools in Homo erectus sites—though there is no evidence that they were intentionally distinguished from other flints or glasses. In China, translucent tektites were called "star rain stones" and appear in historical texts as symbolic materials. Moldavite—the European variant of tektite—has the most documented cultural history: moldavite spearheads were found in Neolithic Central Europe (Lengyel culture, 5000–4500 BCE), indicating recognition of the material as exceptional from very early times. Attributed Properties in Crystal Healing Tektite (transformation and expansion of consciousness) is positioned in modern crystal healing as a catalyst for profound change. The connection between terrestrial material and cosmic impact is the central symbolic argument: it is presented as a bridge between the terrestrial and the cosmic, facilitating a broad perspective in moments of vital transformation. Its dark color also associates it with grounding and protection in various traditions. Chakras and Associations Chakra Element Planet Root (Muladhara), Crown (Sahasrara) Fire, Ether Saturn, Pluto How to Identify Authentic Tektite Basic Tests Conchoidal fracture with curved, sharp edges is characteristic of glass. A corroded or rough surface—with grooves from chemical dissolution—is common in authentic tektites; artificial glass has a smoother surface or mold marks. The density of 2.3–2.5 g/cm³ is lower than that of obsidian (2.4–2.6) and significantly less than that of crystalline silicates like quartz (2.65 g/cm³). Under shortwave UV, many tektites do not fluoresce or do so weakly, while certain imitation glasses exhibit intense fluorescence. In a refractometer, the isotropic RI between 1.46 and 1.54 distinguishes tektites from birefringent minerals. Common Confusions Volcanic obsidian is the most frequent confusion: both are black glasses with conchoidal fracture. The quickest distinction is density (obsidian 2.4–2.6 g/cm³ vs. tektite 2.3–2.5) and water content (obsidian has 0.1–0.3%; tektite less than 0.02%). Manufactured glass imitations have densities of 2.2–2.5 but show visible bubbles or molding marks under magnification. Care and Maintenance Cleaning Clean with a soft cloth and lukewarm water. Do not use acids or abrasive products that could alter the natural corrosion texture, which is part of the specimen's mineralogical value. For carved jewelry pieces, use the same care as with any glass: avoid ultrasonics that could aggravate internal microfractures. Storage Tektites are relatively resistant under normal conditions. Store separately from harder abrasive minerals to prevent scratching the surface. For collector specimens with intact aerodynamic morphology, use an individual padded box to protect the shape. Tektite at Anima Mundi Crystals We work with natural tektites from documented strewn fields, primarily Australites and Indochinites. Uncut natural pieces can be found in rough minerals; cut cabochons, in cabochons. For the most well-known green variant, see the moldavite guide. Frequently Asked Questions about Tektite What is a tektite? A tektite is a natural glass formed by the impact of a large meteorite that melts terrestrial material and ejects it into the atmosphere. As it cools during its return flight, the material solidifies into characteristic aerodynamic shapes. The composition reflects the melted terrestrial crust, not the meteorite itself. Is tektite a meteorite? No. Tektite is formed from terrestrial material melted by impact, not extraterrestrial material. It may contain traces of the projectile in the form of metallic microspheres, but its main composition (SiO₂, Al₂O₃, FeO) is terrestrial crust. Moldavite, for example, is geochemically indistinguishable from Central European Mesozoic sedimentary rocks. What is the difference between tektite and obsidian? Both are dark natural glasses with conchoidal fracture, but of radically different origin. Obsidian is volcanic glass with 0.1–0.3% structural water and a density of 2.4–2.6 g/cm³. Tektite is impact melt glass with less than 0.02% water and a slightly lower density (2.3–2.5 g/cm³). Obsidian is much more abundant and economical. What is moldavite and why is it different? Moldavite is a variety of tektite of intense green color formed 14.7 million years ago by the Nördlingen impact (southern Germany), scattered in Bohemia, Moravia, and Lusatia. Its green color comes from the high SiO₂ content and the specific composition of the melted sedimentary material. It is the most commercialized tektite and has its own complete guide. How to distinguish authentic tektite from a glass imitation? Authentic tektites show a corroded surface with chemical dissolution grooves, natural conchoidal fracture, and absence of melting bubbles. Manufactured glass has a smoother surface or mold marks and usually shows internal bubbles visible with a 10× magnifier. Density and RI are confirmatory parameters in the laboratory. What is tektite used for in crystal healing? The tradition of crystal healing associates tektite with profound transformation and expansion of perspective, linked to the cosmic origin of the mineral. It is used in spiritual work related to significant life changes and the connection between the terrestrial and the cosmic. There are no scientific studies to support these attributions. Recommended Bibliography Koeberl, C. (1994). Tektite origin by hypervelocity asteroidal or cometary impact. Geological Society of America Special Papers, 293, 133–152. Simmons, R., & Ahsian, N. (2005). The Book of Stones. Heaven & Earth Publishing. Glass, B. P., & Simonson, B. M. (2012). Distal Impact Ejecta Layers. Springer. Mindat.org — Tektite: mindat.org/min-3912 Meteoritical Society — Tektites: meteoritical.org

Tektite — Properties, Meaning, and Uses

Anima Mundi CrystalsJun 6, 2026

Information

Property	Value
Mineralogical Name	Tektite (natural impact glass)
Composition	SiO₂ (65–82%) + Al₂O₃, FeO, MgO, CaO, TiO₂
Mineral Group	Natural Glasses (amorphous)
Crystal System	Amorphous (no crystalline structure)
Hardness (Mohs)	5.5–7 (depending on type)
Density	2.3–2.5 g/cm³
Luster	Vitreous
Fracture	Conchoidal (characteristic of glass)
Color	Black, dark brown, olive green (moldavite), yellowish green
Streak	White to colorless
Diaphaneity	Opaque to translucent in thin sheets
Strewn Fields	Australia, Southeast Asia, Eastern North America, West Africa, Central Europe (moldavite)