Rhyolite gemstone beads can look very similar to jaspers, and the popular green variety of rhyolite is sometimes called rainforest jasper. Similarly, the type of rhyolite that displays red, yellow, brown, and pinkish spots is descriptively called leopardskin jasper. In reality, rhyolites are igneous rock that is chemically identical to granite. These beautifully marked semi precious gemstones originated when rhyolitic magma and lava cooled from a molten state too quickly for crystals to form. Variations on the beautiful swirls of green "rainforest" rhyolite include strikingly marked birdseye rhyolite. Rhyolite occurs largely in the U.S.A.