DCHP-1 Online
buffalo stone 
a fragment of a fossil cephalopod, Bacculites, valued by Prairie Indians as a charm.
- 1932 [. . . some Indians on the plains carried curious natural stones shaped like miniature buffaloes to give them good luck and success in hunting.]
- 1954 . . . the "Buffalo Stone" whispers sweet words of encouragement to the faint-hearted.
- 1965 Like many other artifacts, including buffalo stones, they [ribstones] are characteristic of the region as a whole, cross-cutting tribal and linguistic boundaries.
- 1932 [. . . some Indians on the plains carried curious natural stones shaped like miniature buffaloes to give them good luck and success in hunting.]