- Glass is a state of matter.
- Glasses combine some properties of crystals and some of liquids but are distinctly different from both.
- Glasses have the mechanical rigidity of crystals, but the random disordered arrangement of molecules that characterises liquids.
- Glasses are usually formed by melting crystalline materials at very high temperatures. When the melt cools, the atoms are locked into a random (disordered) state before they can form into a perfect crystal arrangement.
The complete description can be seen at the Corning Museum of Glass