Scientifically speaking, the term “crystal” refers to any solid that has an ordered chemical structure. This means that its parts are arranged in a precisely ordered pattern, like bricks in a wall.

Crystals—from sugar and table salt to snowflakes and diamonds—don’t always grow in a straightforward way. New York University researchers have captured this journey from amorphous blob to orderly ...

Crystals can do all sorts of things, some more useful than others. They can separate the gullible from their money in New Age healing shops. But they can also serve as the light-harvesting layer in a ...