What is Glass?

Glass is born from nature’s own ingredients—sand, soda ash, and limestone—it is forged when these raw materials are heated to scorching temperatures. But what makes glass truly remarkable is what happens next. As the molten mixture cools, it doesn’t form a typical crystal structure. Instead, it becomes something unique—neither a solid nor a liquid.

Scientists describe glass not as a material, but as a state of matter. In a crystal, atoms align in an orderly, lattice-like pattern. In a liquid, atoms are free to move chaotically, allowing it to flow. In glass, its atoms are locked in place, unable to flow, but they haven’t had the time to arrange themselves into the perfect order of a crystal. This is why glass is often called a "rigid liquid"—frozen in time between two states.

Though we often associate glass with human innovation, it exists naturally in the wild. When volcanoes release molten rock, when lightning strikes the sand, or when a meteorite crashes into the Earth, glass-like substances are born. Even some sea sponges and certain microscopic algae can create siliceous, glassy skeletons.

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