Learn the definitions to all those jewelry terms you don't know.
This gemstone is composed of hydrated silica spheres which create a pattern of mini rainbows throughout the stone. It is also the birthstone of October. Because it is a relatively delicate gemstone, avoid sharp blows to your opal and keep it away from extreme heat. Opals have a 2-6% water content, so they should always be stored in a cool, protected place.