Glass:: From the First Mirror to Fiber Optics, the Story of the Substance That Changed the World

An excellent book about glass and glass making. The reference to tektites--natural, extraterrestrial glass stones--is all too brief however (and inaccurate in scope). Author William S. Ellis fails to tell the whole story of the on-going--and most certainly unresolved--mystery of tektite origin! Oddly, both sides of the constroversy consider the problem solved. Reading "Glass," one would assume the "impact" side has won the debate. Not true at all! Ellis fails to mention one of the most credible theories of tektite origin: That is, that tektites appear to some geologists and astronomers (and some ceramic scientists)to be extraterrestrial volcanic glass, probably ejected during ancient silicic eruptions on the Moon. Also, the author fails to mention that tektite glass is far too "fined" to have been made in the near-instantaneous force of terrestrial meteorite impacts, as the mainstream "impact" scientists contend. The chemical trends in tektites are clearly igneous, not sedimentary as noted here and stated by the impact people.