— Despite the stone's name, Rainforest Jasper isn't a true Jasper. Instead, it's Rhyolite containing small Spherulites and semi-crystalline areas. These are the dots or sections of different colored minerals inside of the Rhyolite matrix. ... Green Rhyolite, and Spherulitic Rhyolite. Most of the commercial supply comes from Mt. Hay, 23 ...