natural glass

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July 1, 2026

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Natural glass is a silica-rich, noncrystalline solid that originates from volcanic activity or cosmic events. Volcanic glass, such as obsidian, forms when lava cools too rapidly to crystallize. Other natural glasses include fulgurites (formed by lightning strikes), tektites, moldavites, and Libyan Desert glass.1234

These natural glasses are generally unstable and tend to devitrify (crystallize) over geological time. However, their chemical durability, especially that of microtektites found underwater, is of commercial interest for applications like hazardous waste immobilization.24

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industrial glass
Natural glasses
Several inorganic glasses are found in nature. These include obsidians (volcanic glasses), fulgarites (formed by lightning strikes), tektites found on land in Australasia and associated microtektites from the bottom of the Indian Ocean, moldavites from central Europe, and Libyan Desert glass from western…
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Several inorganic glasses are found in nature. These include obsidians (volcanic glasses), fulgarites (formed by lightning strikes), tektites found on land in Australasia and associated microtektites from the bottom of the Indian Ocean, moldavites from central Europe, and Libyan Desert glass from western…
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feldspar
Glass forms when magma (molten rock material) is quenched—i.e., cooled so rapidly that the constituent atoms do not have time to arrange themselves into the regular arrays characteristic of minerals. Natural glass is the major constituent of a few volcanic rocks—e.g., obsidian. Macerals are macerated…
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Glass forms when magma (molten rock material) is quenched—i.e., cooled so rapidly that the constituent atoms do not have time to arrange themselves into the regular arrays characteristic of minerals. Natural glass is the major constituent of a few volcanic rocks—e.g., obsidian. Macerals are macerated…
Read More