What is a Crystal?

A crystal is a mineral in its most stable form. It has a recognizable structure made up of repeating arrangements of atoms known as a crystal lattice. Crystals are the most organized and stable matter in the universe. Crystals only form from a gas or liquid solution at the correct temperature and pressure. Once crystallized a mineral can remain unchanged for millions of years. Crystals can grow to a huge size or appear too small to be seen by the naked human eye.