Lithium in tektites and natural glasses

Lithium concentrations in various tektites and natural glass samples have been determined using RNAA. For most tektites Li abundances range from 40 to 60 ppm, with the exception of bediasites (23 ppm). In other natural glasses of presumed impact origin, the Li values are considerably lower (6 to 11 ppm). It is suggested that the Li concentrations reflect mostly the original abundance of this element in parent materials. A terrestrial origin for tektites is supported by the Li range overlap between tektites and sedimentary rocks. (author)