Myths and Legends of our Own Land, by Charles M. Skinner, , at sacred-texts.com
Pipestone, a smooth, hard, even-textured clay, of lively color, from which thousands of red men cut their pipe-bowls, forms a wall on the Coteau des Prairies, in Minnesota, that is two miles long and thirty feet high. In front of it lie five bowlders, the droppings from an iceberg to the floor of the primeval sea, and beneath these masses of granite live the spirits of two squaws that must be consulted before the stone can be dug. This quarry was neutral ground, and here, as they approached it, the men of all tribes sheathed their knives and belted up their axes, for to this place the Great Spirit came to kill and eat the buffalo, and it is the blood of this animal that has turned the stone to red. Here, too, the Thunder Bird had her nest, and her brood rent the skies above it with the clashing of their iron wings.
A snake having crawled into this nest to steal the unhatched thunders, Manitou caught up a piece of pipestone, hastily pressed it between his hands, giving it the shape of a man, and flung it at the reptile. The stone man's feet stuck fast in the ground, and there he stood for a thousand years, growing like a tree and drawing strength and knowledge out of the earth. Another shape grew up beside him—woman. In time the snake gnawed them free from their foundations and the red-earth pair wandered off together. From them sprang all people.
Ages after, the Manitou called the red men to the quarry, fashioned a pipe for them, told them it was a part of their flesh, and smoked it over them, blowing the smoke to north, south, east, and west, in token that wherever the influence of the pipe extended there was to be brotherhood and peace. The place was to be sacred from war and they were to make their pipes from this rock. As the smoke rolled about him he gradually disappeared from view. At the last whiff the ashes fell out and the surface of the rock for miles burst into flame, so that it melted and glazed. Two ovens opened at its foot, and through the fire entered the two spirits Tsomecostee and Tsomecostewondee—that are still its guardians, answering the invocations of the medicine-men and accepting the oblations of those who go to make pipes or carve their totems on the rock.