We have measured the 1/f noise of simultaneously and identically prepared submicron-scale gold samples with none or only a few grain boundaries. We consistently observed that the samples with the lowest number of grain boundaries produced the lowest noise. In addition, micron-scale single-crystalline gold samples when measured displayed about (1/3) of the noise of similar polycrystalline samples. This is strong evidence that a significant part of the 1/f noise of a gold sample is related to atomic motion near or along a grain boundary. © 1987 The American Physical Society.