Nearby features include Crater Butte, a basaltic andesite cinder cone volcano to the southeast, and Redtop Mountain, to the east and composed of basalt. Both mountains are likely close to the same age as Diamond Peak, and are formed by layers of red and black lapilli, scoria, and volcanic bombs. The earliest strata have been converted to palagonite with a yellow-orange color that was derived from volcanic glass. Emigrant Butte, a basaltic andesite peak to the south, has been altered more extensively by glaciers, and therefore is likely older. Mount Yoran is a significantly older mountain made from basaltic andesite lava that has a summit protruding from the northern slope of Diamond Peak. It has been potassium-argon dated to be between 520,000 and 220,000 years old. A shield volcano,[b] Yoran is often considered one of the subfeatures of Diamond Peak, along with the Diamond Rockpile cinder cone and Crater Butte. Yoran and the nearby stratovolcano Lakeview Mountain have similar compositions to Diamond Peak, with dissected cones made of pyroclastic material with embedded lava flows. Both volcanoes have been invaded with sills fed by dikes that can be traced to nearby volcanic plugs.