Carbon Peak is a 12,088-foot summit in Colorado’s West Elk Mountains, southwest of Crested Butte in Gunnison National Forest, and one of the range’s prominent laccoliths. It formed about 30 million years ago when magma intruded the sedimentary layers of the Mesaverde Formation, creating a dome of resistant igneous rock later exposed as erosion removed softer layers above it. Made of quartz monzonite porphyry and granodiorite porphyry, the mountain also bears evidence of later glaciation, especially a notable cirque on its north side. Its name reflects coal in the Mesaverde Formation, and the peak is valued as a clear expression of the region’s geologic history.