Crystal Peak Dolomite is a Middle Ordovician geologic formation in the Wah Wah Mountains of western Utah’s Great Basin, named for exposures at Crystal Peak. Composed chiefly of brown to gray or black dolomite, it is generally fine- to medium-grained, with some coarser beds. Measured sections range from 61 to 92 feet thick, including 89 feet at Crystal Peak, and contain a thin layer of quartz sandstone and siltstone above the base. The unit lies between the Watson Ranch Quartzite tongue of the Swan Peak Quartzite and the younger Eureka Quartzite. Fossils including orthocone cephalopods and Eofletcheria corals make it an important fossil-bearing Ordovician formation.