Crystal (noun)

1. A solid material in which the atoms, molecules, or ions are arranged in an orderly repeating pattern extending in all three spatial dimensions.
2. A piece of a clear, transparent mineral, such as quartz, used in jewelry and decoration.
3. A piece of glass or plastic in the shape of a crystal, used in chandeliers and other decorations.

Origin:

From middle english cristal, from old french cristal, from latin crystallus, from ancient greek κρύσταλλος (krustallos, "ice, clea.r")

Examples:

1. The crystal glass sparkled in the light.
2. The crystal structure of the mineral was studied.
3. The chandelier had crystal pendants.
4. The watch had a crystal face.
5. The crystal vase was beautiful.