DCHP-1 Online
rocker ((1)) † Placer Mining 
n. a contrivance used to separate gold from gravel.
See also: cradle-rocker rock (out) rocking
- 1859 I saw the product of many of the rockers, and found that the daily yield to each rocker was from ten dollars to two ounces; in some instances a much larger yield.
- 1927 Each night the rockers were "cleaned up" and the gold was collected, the finer particles being separated from the metallic black sands by the use of mercury.
- 1965 [Caption] A rocker set up to rework old tailings at Cedar Creek.
- 1859 I saw the product of many of the rockers, and found that the daily yield to each rocker was from ten dollars to two ounces; in some instances a much larger yield.