© Oxford Dictionary of Rhymes 2007, originally published by Oxford University Press 2007.Oxford Dictionary of Rhymes Oxford University Press
Copyright The Columbia University PressThe Columbia Encyclopedia, 6th ed. The Columbia University Press
bluestone, common name for the blue, crystalline heptahydrate of cupric sulfate called chalcanthite, a minor ore of copper. It also refers to a fine-grained, light to dark colored blue-gray sandstone. Deposits are extensively quarried as flagstone (paving stone) in New York and Pennsylvania and used commercially for buildings and paving stone.