The width of Raymond mill is generally 50-300m or wider, and the length can reach several kilometers or even tens of kilometers; generally it is made up of soft sandstone; the buried depth of the ore is generally 1-5m, some would 20-30m even deeper; the thickness of the gold-bearing ore layer is usually 1-5m; the bottom of gold layer is mostly granite, shale, limestone.

Associated mineralsIn addition to gold, Raymond mill also contain a variety of heavy minerals, which associated with gold, magnetite, ilmenite, rutile, garnet, zircon, hematite, chromite, olivine, epidote, pyrite, monazite, limonite, platinum, antimony, cinnabar, wolframite, scheelite, cassiterite, corundum, diamond, mercury paste, galena, etc.

In the placer gold deposit, heavy minerals usually does not exceed 1-3 kg/m3, and the rest are gravel, pebbles, sand and clay.

Clay is not good for the fine-grained gold recovery process and should be removed before the gold selection process.