5 oz LIBYAN DESERT GLASS Meteorite Art Silver Coin 5000 Frs Chad 2017

This beautiful 5 Oz Silver coin is the third issue in the “Meteorite Art” series and features a genuine Libyan Desert glass, cut and polished to showcase its beautiful structure. Libyan Desert glass, or Great Sand Sea glass is an impactite found in areas in the eastern Sahara, in the deserts of eastern Libya and western Egypt. Fragments of desert glass can be found over areas of tens of square kilometers where the wind has exposed large areas of bedrock.

The origin of desert glass is uncertain. Meteoritic origins have long been considered possible, and recent research links the glass to impact features, such as zircon-breakdown, vaporized quartz and meteoritic metals, and to an impact crater. Some geologists associate the glass with radiative melting from meteoric large aerial bursts, making it analogous to trinitite created from sand exposed to the thermal radiation of a nuclear explosion. Libyan Desert glass has been dated as having formed about 26 million years ago. It was knapped and used to make tools during the Pleistocene.

Usually an opaque yellow in colour, Libyan Desert Glass is thought to be the purest natural silicate glass to be found anywhere on Earth. The largest piece ever found weighed a hefty 26 kilograms in weight, but most fragments are the size and shape of polished pebbles. Over a thousand tons of this glass is believed to be strewn over this area.