Crystalline structure' means made up of crystals. What's inside Crystals Ions, atoms and molecules make up crystals. All matter on Earth is made of atoms. Molecules in a crystal are held tightly together, but they still vibrate because of thermal energy. Melting is a phase change.
Ice has heat energy.
In this report, there are facts about crystals. For example, what's inside crystals, the study of crystals, crystal's history, formation and shapes and kinds.