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
Dedham Granite Dedham Granite Dedham Granite is a light grayish-pink to greenish-gray, equigranular to slightly porphyritic, variably altered, granite south and west of Boston, named for the town of Dedham, Massachusetts. Dedham Granite includes dioritic rock near Scituate and Cohasset and Barefoot Hills Quartz Monzonite. Intrudes Zdi, Zgb, Zb, Zv. Extensive calc-alkaline plutons separated by Boston basin have long been mapped as Dedham. Those to the north of Boston and studied by the US Geological Survey, are referred to as Dedham North. Crystallization ages for the Dedham North suite (based on titanites and zircons) have been determined at 607+/-4 Ma, while ages