The origin of tektites - A brief review

The controversy surrounding tektites is re-examined, their imputed lunar origin is definitively rejected, and their origin as impact glass produced from terrestrial rocks melted by hypervelocity impacts of large, extraterrestrial objects is defended. Some of the extensive literature on tektites is grouped according to the origin ascribed to the tektites in the papers (as glass meteorites or other extraterrestrial origins, as lunar ejecta, or as terrestrial impact glass). The mineralogy, morphology, and chemistry of tektites are discussed, and associations with ancient impact craters (such as the Ries basin in SW Germany) are indicated. The dissimilarity of tektites and lunar samples studied is considered definitive; some remaining problems are pointed out (crater associations, impact velocities and ejecta velocities, distribution).