On Tektites and Pseudo-tektites from Dutch East Indies and Philippines

Dr. Kuiper and Dr. Nieuwenkamp collected remarkable, etched pieces of dark glass, strongly resembling tektites, in Patagonia. Dr. Ph. H. Kuenen director of the geological institute of the Rijksuniversiteit at Groningen kindly put them at our disposal for investigation. They are now in the Rijksmuseum van Geologie en Mineralogie of Leiden. The chemical analysis and the optical examination showed that these objects are not tektites, but pebbles of volcanic glass. From Palembang pebbles of obsidian are known, which might be taken for tektites by a layman in these matters, but not by an expert. These pebbles were collected by Prof. Dr. B. G. Escher in 1917 in South-Palembang, Boorterrein Soengei Taham near Moeara Enim, on account of their interesting sculpture. They were analysed together with the well-known obsidian from Goenoeng Kiamis near Garoet (collected by Escher in 1929) and were found to bear much resemblance in chemical respect.