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Last update: May 10, 2012
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| Libyan Desert Glass, 37.5 g, gem quality piece |
On December 29, 1932
Patrick Clayton, a British explorer, discovered a mysterious yellow-green glass scattered across the surface in an area of
western Egypt, at the edge of the Libyan Sand See, one of the most remote and inhospitable regions on earth. Ever since, Libyan
Desert Glass has fascinated scientists, who puzzled over its formation.
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| Libyan Desert Glass, stunning gem quality piece, 85.8 g |
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| Libyan Desert Glass, gem quality piece with some dark streaks on the left side, 25.8 g |
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| Libyan Desert Glass, gem quality with interesting dark inclusions, 26.6 g |
Libyan Desert Glass is a natural glass composed of nearly pure silica (98 wt %), the purest natural glass in the world. This purity
gives the glass some remarkable properties. It can be heated up to 1700° C before it begins to melt, over 500°C higher than
other natural glasses. It can be dropped into water when red hot and it will not disintegrate. The formation of this glass, because
of its unusual composition has for long been considered as mysterious.
Some of the glass has inclusions like
bubbles, spherules of cristobalite (a high temperature silica polymorph), and rarely dark streaks. Chemical analyses of these
dark inclusions show that they are enriched in meteoritic elements, with typical chondritic proportions. So the best explanation
for these observations is that the glass results from a meteorite impact on a silica-rich target.
Koeberl: Confirmation of a Meteoritic Component in Libyan Desert Glass
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| Libyan Desert Glass, gem quality piece with very rare and interesting dark inclusions, 19.5 g |
The glass can be milky from thousands of bubbles or gem quality with almost no impurities.
Libyan Desert Glass was formed 29 million
years ago, very likely when an asteroid or comet hit the surface of the earth like a huge atomic bomb, unleashing enough destructive
force to liquefy the rocks, sand and dirt at ground zero. The crater marking the original impact site has not yet been discovered. It‘s possible that
it is under millions of tons of sand or it erroded away over the millions of years. Another possibility is that an event,
similar to the explosion of an asteroid or comet that knocked down nearly a thousand square miles of trees in the Tunguska
region in Siberia on June 30, 1908. A similar, much larger, atmospheric explosion could have created a fireball that would
be large and hot enough to fuse surface materials to glass, much like the first atomic explosion generated green glass at
the Trinity site in 1945.
In 1998 an Italian scientist, Vincenzo de
Michele, visited the Egyptian Museum in Cairo and noticed that one of King Tutankhamun’s jeweled breastplates contained
a carved scarab that looked suspiciously like a piece of the glass. A simple optical measurement confirmed that it was made
of Libyan Desert Glass!
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| Libyan Desert Glass, gem quality piece with interesting layers, 14.4 g |
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| Libyan Desert Glass, artifact, gem quality piece with great shape, 19.9 g |
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| Libyan Desert Glass, artifact, gem quality piece with interesting shape, 15.5 g |
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| Libyan Desert Glass, gem quality piece with Cristobalite inclusions, 34.9 g |
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| Libyan Desert Glass, gem quality, five very nicely shaped artifacts, about 5 - 12 g each |
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| Libyan Desert Glass: Several pieces show these kind of marks. How did they form? |
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