Satisfy your desire for the whole rainbow with agate beads!
Agate is a variety of chalcedony, which is itself a form of quartz. Agate displays distinct banded patterns. There are a multitude of agate varieties specific to locations all over the world.
Metaphysically, Agates are generally thought of as stabilizers and bring calm energies to their wearers. The protective capabilities of agate have been utilized since ancient times, often in the form of amulets and talismans.