PELLETING. The transformation of a soft, often dusty feed into a hard pellet is accomplished by compression, extrusion, and adhesion. The general process involves passing a feed mixture through a conditioning chamber where 4 to 6 percent water (usually as steam) may be added.
The industrial infrastructure comprised 22 lagunas or reservoirs, from which a forced flow of water produced the hydraulic power to activate the 140 ingenios or mills to grind silver ore. The ground ore was then amalgamated with mercury in refractory earthen kilns called huayras or guayras.