Abstract: A protocol for characterizing a rock is provided. The protocol includes a crushing operation, wherein a test column of the rock in granular form is subjected to a compressive force orientated parallel to the axis of the column. The protocol further includes a measurement operation, wherein the amount by which the axial length of the test column is reduced through the application of the force is measured. The protocol yet further includes a calculation operation, wherein a characteristic of the rock is calculated using the product of the force applied and the amount by which the length of the test column is reduced through the application of the force. A method for characterizing the hardness of a subject rock is also provided.

Abstract: A protocol for characterizing a rock is provided. The protocol includes a crushing operation, wherein a test column of the rock in granular form is subjected to a compressive force orientated parallel to the axis of the column. The protocol further includes a measurement operation, wherein the amount by which the axial length of the test column is reduced through the application of the force is measured. The protocol yet further includes a calculation operation, wherein a characteristic of the rock is calculated using the product of the force applied and the amount by which the length of the test column is reduced through the application of the force. A method for characterizing the hardness of a subject rock is also provided.

Abstract: A process for recovering a base metal from a material, the base metal being selected from cobalt, copper, nickel and zinc, the process comprising the steps of reacting the host material with a ferric ion species in a leach solution, at conditions sufficient to cause at least a portion of the base metal to be oxidized by the ferric ion species, thereby causing the ferric ion species to be converted to a ferrous ion species, and oxidizing the ferrous ion species with an oxidation mixture of SO2 and oxygen to form the ferric ion species for subsequent reaction with the material.

Abstract: A device for measuring free acid concentrations in a solution bearing an ionic constituent therein, forms a test sample of the solution and measures the concentration of the ionic constituent in solution in the test sample. The device measures conductivity of the test sample and calculates the concentration of free acid in the test sample based on the conductivity and the concentration of the ionic constituent in solution.