The bloody gem from an Uktena's head:

 “It is a large transparent crystal, nearly the shape of a cartridge bullet, with a blood-red streak running throughout the center from top to bottom. The owner keeps it wrapped in a whole deerskin, inside an earthen jar hidden away in a secret cave in the mountains. Every seven days he feeds it with the blood of small game, rubbing the blood all over the crystal as soon as the animal has been killed. Twice a year it must have the blood of a deer or other large animal. Should he forget to feed it at the proper time it would come out of its cave in a shape of fire and fly through the air to slake its thirst with the lifeblood of the conjurer or some one of his people. He may save himself from this danger by telling it, when he puts it away, that he will not need it again for a long time. It will then go quietly to sleep and feel no hunger until it is again brought forth to be consulted. Then it must be fed again with blood before it is used.

No white man must ever see it and no person but the owner will venture near it for fear of sudden death. Even the conjurer who keeps it is afraid of it, and changes its hiding place every once in a while so it can not learn the way out. When he dies it will be buried with him. Otherwise it will come out of its cave, like a blazing star, to search for his grave, night after night for seven years, when, if still not able to find him, it will go back to sleep forever where he has placed it. Whoever owns the Ulun'suti is sure of success in hunting, love, rainmaking, and every other business, but its great use is in life prophecy. When it is consulted for this purpose the future is seen mirrored in the clear crystal as a tree is reflected in the quiet stream below it, and the conjurer knows whether the sick man will recover, whether the warrior will return from battle, or or whether the youth will live to be old."

James Mooney, Myths of the Cherokee

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