Libyan Desert Glass is believed to the result of the impact of a large meteorite, or the result of a significant aerial burst explosion around 28.5 million years ago (dated by the fission track method). They are the purest form of natural glass on earth, containing over 96% silica. They were first discovered by ancient Egyptians as evidenced by a scarab beatle carvings found on the mummy of King Tutankhamun. Today they are found in the deep Saharan desert, two days driving into a militarized zone near the border of Libya and Egypt. The leading theory leans towards an aerial burst ten thousand times more powerful than the Hiroshima nuclear detonation (Boslough). Some pieces have dark streaks; chemical analyses of these inclusions show enrichment by meteoritic elements, such as Osmium, with typical chondritic proportions (Koeberl C.). 

These two pieces were used as scrapers by nomadic man approximately 10,000 years ago. Holding these  will blow your mind. It started as sand/precambrian sandstone, was melted by an aerial burst into glass, laid around for 28 million years. Was then picked up and fashioned into a tool by paleolithic man and used to scrape animal hides, dropped and found again recently. These two are fine examples as they have natural curves and obvious edges. It fits in the right hand perfectly. You too will want to scrape hides when you hold this remarkable artifact! The large is 13 grams, the smaller is 5 grams (3 x 2 cm). There is a chip or two near the blade edge on each.