The following estimates are for counter-current decantation cyanide circuits and are based on average grade ore requiring average treatment time. These include precipitation and accessory equipment. The equipment required for a cyanide plant will vary considerably with the value of the ore, the settling rate, the chemical composition of the ore, the hardness, and the degree of grinding required, as well as other important factors. It is very difficult to give accurate estimates on a cyanide mill until the exact flowsheet has been determined. There are so many factors that enter into the cost of a cyanide mill that the following figures must be carefully checked so that ample consideration is given to all these variable factors.