Glassy, molten rocks can also be produced directly by the high heat and pressure of a meteorite impact or just its shock wave, without projecting the molten material up into our atmosphere. Molten glass and rocks fractured by high pressure have been found near impact craters. The Ries Crater in southern Germany has molten rocks containing high pressure forms of silica, while other sites have 'shocked' quartz showing strain and fracturing, pulverised rock flour and shock breccia (rock fragmented and compacted by shock). Sometimes a yellow glass made from fused quartz sand is found in desert areas, 'Libyan glass' from the Libyan desert being a well-known example. Such examples are probably a result of an impact, but there may not be direct evidence of associated craters.
In the Northern Territory of Australia, small rounded pieces of frothy, molten rock have been found at the Henbury craters, and rocks fractured into a regular 'shatter cone' pattern by intense, sudden pressure have been found at Gosses Bluff impact crater. Mt Darwin crater near Queenstown, Tasmania has molten glass (' Darwin glass') very much like tektites, but it has probably not travelled through our atmosphere.
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