Yule Marble is found in the West Elk Mountains of Colorado near the town of Marble, Colorado (39°4′20″N 107°11′22″W? / ?39.07222°N 107.18944°W? / 39.07222; -107.18944). It is famous for its uniform pure white consistency, lacking, for the most part, the gray streaking commonly found in other marble such as that found in Vermont. The rock is named for George Yule, a mining engineer who discovered and realized the value of the marble deposit. The Yule Marble deposit is among the largest in the world and, at 99.5% pure calcite, it is one of the purest marbles ever quarried. Yule Marble was declared the official Colorado state rock in 2004. The same year, the quarry was acquired by Polycor.