Abstract
Fission damage induced in calcite is shown by etch pits developed with weak acid at the damage sites. The damage can be differentiated from dislocations by annealing. By this method we have observed fossil fission damage in natural samples. Thus, some etch pits previously attributed to dislocations actually result from such damage. Annealing studies indicate that the damage should persist for about 4 x 107 years at 50°C, and direct evidence suggests that the fission damage has persisted for at least 104 years in one specimen.
