26 Mar 2014
Understanding why gold classification is important
Classification is an essential part of good recovery technique, but understanding why to classify is equally important. Most miners classify to reduce large rocks from building up in their sluice. Classifying also allows you to reduce the water flow and pitch of your sluice bed. Smaller / lighter material requires less “force” to push it down and out.
Reduce water flow and pitch by classifying
Most miners will have riffles in their sluice. Larger rocks can easily stop in front of, behind, or between these riffles. When this happens, the ARMP (active reduction and minimization process) action of the sluice is effectively reduced to zero. Vortexes collapse, matting is covered, and no flow is occurring.
By classifying down to very small material, you can reduce the water flow and pitch, which creates a better “sluice environment” for catching gold, especially fine gold.