Marston Ranch Jasper probably has its origin as petrified wood. The wood structure has been lost, so it would be more properly referred to as a limb cast. Nonetheless, this jasper has bright contrasting red, yellow and green colors that create superior gemstones and slabs. PLEASE NOTE: Marston Ranch Jasper often has vugs and fractures. . Jasper is an opaque, microcrystalline form of quartz. As with any microcrystalline quartz, it is hard and takes an excellent polish with cerium or tin oxide.