Conway granite Conway granite Conway granite is a typically pink mineral-rich igneous (or mesoperthitic) biotite granite. It is amphibole-free and of coarse particle size (with portions of the rock fine-grained or porphyritic). Conway granite has a relatively high concentration of thorium, at about 56 (±6) PPM; this amount is not enough to make the granite dangerously radioactive, but it is sufficient to make the rock a low-grade (almost certainly not economic, at least in the early years) source of thorium for a thorium fuel cycle. Geologist Edward Hitchcock named the granite in 1877 after the town of Conway, New Hampshire, which is
El Capitan Granite El Capitan Granite El Capitan Granite is a type of granite (also see granodiorite), in a large area near El Capitan, in Yosemite National Park, California, United States. The granite forms part of the Tuolumne Intrusive Suite (also known as Tuolumne Batholith), one of the four major intrusive suites within the Sierra Nevada. El Capitan granite is mostly unjointed. The granite has abundant quartz, plagioclase, crystals of orthoclase, and both feldspars — orthoclase and plagioclase — are white. Hornblende is rare, compared to other Yosemite granites. Most black minerals are biotite. It is found west of Half Dome Granodiorite, both