Pipestone

Pipestone, or catlinite, is a fine-grained argillite, a mudstone altered by heat and pressure, usually brownish red, that lies in beds within the hard Sioux Quartzite. Fresh Minnesota stone comes out of the ground pinkish and soft enough to cut with a hacksaw or a knife, and the iron compounds that colour it break down if it is left open to the weather. Being easy to carve, it has long been valued by the Plains nations for ceremonial pipes. The quarries outside Pipestone, Minnesota, are protected as Pipestone National Monument, where only enrolled Native Americans may dig it, and with hand tools alone. The name catlinite honours the painter George Catlin, who visited the quarries in 1835, though Philander Prescott had written about the rock in 1832. Wikipedia notes that other pipe-making stones are called pipestone too, among them Utah pipestone and the black stone the Ojibwe also use. Cunningham gives the Sioux name Inyan-sha, red rock, and assigns it to Mars, the Sun and fire. He retells a Sioux account in which the stone is the hardened blood of people lost in a great flood, says it stands for the Sioux themselves and for the North, and asks anyone who has a piece to treat it as sacred and respect Sioux and Omaha ways: it may go in a medicine bag or on the altar, including for peace rituals, but he would never wear it.