Lot of three pieces of natural glass, one being Libyan desert glass and two being Darwin glass. Libyan desert glass's origins is a controversial issue for the scientific community, w/many theories. Meteoric origins for the glass were long suspected, and recent research linked the glass to impact features, such as zircon-breakdown, vaporized quartz and meteoric metals, and to an impact crater. Libyan desert glass has been dated as having formed about 26 million years ago. Specimen measures 1-1/8x.75x.5" and has light olive coloring. This specimen was found in the sands of the Libyan Desert near the Gilf Kebir Plateau in Egypt. The specimen's exterior is smoothed, the result of countless years of sandblasting by desert winds. Rarely is Libyan Desert Glass as translucent and as beautiful as the specimen offered here, which shows only a few inclusions of foreign matter within. Other two specimens are Darwin glass, a natural glass found south of Queenstown in West Coast, Tasmania. It takes its name from Mount Darwin in the West Coast Range, where it was first reported, and later gave its name to Darwin Crater, a probable impact crater, and the inferred source of the glass. The specimens measure 1x1.75x1", weighs 26.65 grams; 1-3/8x2.25x.75", weighs 30.47 grams and both were found in the Mount Darwin crater in Tasmania. From the Robert M. Overstreet Collection and comes with COA.