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Libyan desert glass or Great Sand Sea glass is an impactite, made mostly of lechatelierite, [1] 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. Like obsidian, it was knapped and used to make tools during the Pleistocene. [2]
Microtektites are typically found in deep-sea sediments that are of the same ages as those of the four known strewn fields. [ 3 ] [ 4 ] Microtektites of the Australasian strewn field have also been found on land within Chinese loess deposits, and in sediment-filled joints and decimeter-sized weathering pits developed within glacially eroded ...
Sea glass is physically polished and chemically weathered glass found on beaches along bodies of salt water. These weathering processes produce natural frosted glass. [1] Sea glass is used for decoration, most commonly in jewellery. "Beach glass" comes from fresh water and is often less frosted in appearance than sea glass.
The color of the glass is a pale bottle green, and the material is extremely vesicular with the size of the bubbles ranging to nearly the full thickness of the specimen." [ 3 ] The most common form of trinitite is green fragments of 1–3 cm thick, smooth on one side and rough on the other; this is the trinitite that cooled after landing still ...
Space weathering is the type of weathering that occurs to any object exposed to the harsh environment of outer space. Bodies without atmospheres (including the Moon , Mercury , the asteroids , comets , and most of the moons of other planets) take on many weathering processes:
The tendency for a material to form a glass while quenched is called glass-forming ability. This ability can be predicted by the rigidity theory . [ 13 ] Generally, a glass exists in a structurally metastable state with respect to its crystalline form, although in certain circumstances, for example in atactic polymers, there is no crystalline ...
In chemistry, the term chemically inert is used to describe a substance that is not chemically reactive.From a thermodynamic perspective, a substance is inert, or nonlabile, if it is thermodynamically unstable (positive standard Gibbs free energy of formation) yet decomposes at a slow, or negligible rate.
Diatoms generate about 20 per cent of the oxygen produced on the planet each year, [12] take in over 6.7 billion metric tons of silicon each year from the waters in which they live, [13] and contribute nearly half of the organic material found in the oceans. Diatoms are enclosed in protective silica (glass) shells called frustules.