Peridot

Peridot is one of those gemstones with a genuinely fascinating story. It's gem-quality Olivine — a silicate mineral — and one of the very few gemstones that comes in only one color: olive green. The intensity and shade of that green depends on how much iron is in the crystal structure, ranging from bright yellow-green to deeper, richer olive tones. It's also one of the few gemstones found in meteorites — peridot crystals have been collected from space rocks that have landed on Earth. The principal source of fine peridot is Arizona, though it's also found in Hawaii, Arkansas, Pakistan, Egypt and Norway. It's August's birthstone, and reportedly Cleopatra's personal favorite gemstone.