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SILICA GLASS
LIBYAN DESERT GLASS
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SINCE I SAW THIS BEAUTIFUL GLASS THE FIRST TIME - I WAS FASCINATED - FINALLY ON THE GILF KEBIR
TRIP 2002 I GOT THE CHANCE TO COLLECT SOME PIECES OF SILICA GLASS FOR MY COLLECTION - NEXT TO DESERT STONES AND SHELLS, SILICA WILL ALWAYS HAVE ITS SPECIAL PLACE. |
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LIBYAN DESERT GLASS - AN UNIQUE TECTITE OR IMPACTITE ?
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WHAT IS SILICA GLASS ?
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Silica Glass is a naturally occurring glass. Natural glass can be formed by lightning strike (fulgurite) or
volcanic activity (obsidian), as well as by meteroites striking the earth (tectite and impactite). Silica glass is composed primarily of silicon (up to 98 %). |
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HOW IS SILICA GLASS FORMED ?
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Scientists continue to debate exactly how silica glass is formed. The source in Egypt's Great Sand Sea is
unique in the world. It's one of the most remote and inhospitable regions in the Sahara. It is assumed that the glass here formed when a meteorite struck some 29 million years ago, although no crater can be seen in the area. Some are of the opinion that volcanic debris from the moon or even from Mars was flung into space, captured by the earth's gravitational force, and finally fell into the Libyan Desert. At any rate there is agreement that silica glass formed here as a result of an unimaginably powerful cosmic event. |
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DISCOVERIES
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The Englishman Patrick A. Clayton discovered the source in 1932 and brought the first examples back to
Europe for study. However since 1998 it is known that silica glass was known long before Clayton. Among Tutankhamuns's treasures is a pectoral which contains a silica glass scarab. An Italian mineralogist examined the scarab with the latest equipment to determine the index of refraction and the mineral's structure. The results were surprising. The scarab was without a doubt cut from Libyan desert silica glass. See also THE STONE OF TUTANCHAMUN. |
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SOURCE AND COMPOSITION
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The only source of this glass worldwide is at the southern end of the Great Sand Sea in the area near the
Gilf Kebir. Knowledge of the desert and the right equipment is required to reach the area. The glass is found in an area approximately 130 km by 53 km, among dunes that can reach as high as 100 metres. Wind driven desert sands now sculpt, shape an polish fragments of this rare, exotic glass into strikingly beautiful and unique specimens.
There are pieces in the most diverse sizes, from centimetre-sized pieces to stones weighting some
kilogramms (the biggest ever found piece weight around 28 kg). The surface can vary from smooth pieces polished by the sand to rough uneven examples. Each glass is different and colours vary from milky grey- white to light green and yellow. Silica glass is one of the most rare minerals on earth - even more rare than diamonds. |
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WILL CONTINUE ......
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