Virtually all rocks have mineral crystals, but some are too tiny to be visible. Rocks with visible crystals sometimes reflect light from the crystal faces, making it sparkle.
The "ideal" diamond crystal is called an octohedron. If you take two - four sided pyramid shapes and put them together at the base, that's an octohedron. Square around the center "equator" and...
The reason a person looks the way they do is because of genes from the mother and father of the person. If someone has more weight than another it's either because they let them self go or they're...