Shaker-Concentrator

Shaker-Concentrator. . The shaker-concentrator, also known as a shaker table, was used in gravity beneficiation (the concentration of ore) for sorting fine-grained materials, such as heavy cinnabar, from ordinary rock and dust particles. The beneficiation process was carried out on the surface of the shaker bed, which has a slight tilt. The particles to be separated were fed into the shaker from a trough above the bed. At the same time water was applied to the bed from a tank (or simply a garden hose). Due to combination of gravity, inertia, friction and horizontal flow of water, the particles were stratified according to weight and size; heavier material (in the case of cinnabar) moved slower that lighter material, and thus the material were separated., The exact use of this concentrator from the Guadalupe mine is not known. Concentrators were sometimes used to separate free mercury from the dust captured in the cyclone collector at the output of the rotary furnace or heavy cinnabar from the dust of crushed rock. Old dump rock discarded by miners in the 1800’s was, in their opinion, low-grade ore. In the 1900’s the low-grade rock was considered valuable. The crushing of old dump rock and the concentration of fine rock was often tried, but with mixed results. After 1942, hand sorting and roasting the old rock in rotary furnaces proved to be more economical.