Prepare Gold Ore Sample for Laboratory Testing

Before an ore is tested for its amenability to the cyanide process, it should be subjected to a preliminary examination in order that the experimenter may become familiar with its general physical and chemical characteristics. Knowledge so obtained will be of value in laying out the most effective testing program and may point to special […]

How to Sample Gold Ore

gold_sample_size_formula

The value of any series of experiments depends entirely upon the kind of sample of ore provided for the test. It must represent, wholly and completely, the character of the material that will be treated in the plant to be designed and constructed. If it does not, the tests will be useless or, worse, misleading. In […]

How to use a Microscope to Help Solve Gold Metallurgy

Gold_metallurgy_under_microscope

The assistance that can be obtained from the microscope in solving ore-dressing problems has been increasingly appreciated in the recent years, as attested by the frequency of papers on the subject. Observations by means of binocular microscopes with magnifications up to 100 diameters and corresponding resolutions have long been common practice, and such observations are a great […]

Analytical Methods for Total Cyanide Assay Determination

QC Operation

SCOPE AND APPLICATION The method is designed to determine the concentration of total cyanide in aqueous/water and soil/sediment samples taken from hazardous waste sites. SUMMARY OF METHOD Aqueous/Water and Soil/Sediment The cyanide as hydrocyanic acid (HCN) is released from cyanide complexes by means of a reflux-distillation, using either a midi- or micro-distillation process, and absorbed […]

Cyanide Destruction Methods and Processes

Process Water Treatment Options for Cyanide Destruction

Detoxification processes are used to reduce the concentrations of toxic constituents in tailings streams and process solutions, either by dilution, removal, or conversion to a less toxic chemical form (sometimes referred to as“destruction” or “degradation” in the case of toxic cyanide species). The objective is to produce an effluent that meets limits or guidelines that have been set […]

Gold Amalgamation Equipment

AMALGAM PRESS The Amalgam Press is used wherever the process of amalgamation is practiced. The amalgam is wrapped in a wet chamois skin and inserted in the press, which extrudes the surplus amalgam. The press consists of a steel cylinder, slotted on the sides and perforated on the bottom. The steel piston is forced into […]

Heap Leaching

Heap Leaching Diagram

Heap leaching of gold and silver ores is conducted at approximately 120 mines worldwide. Heap leaching is one of several alternative process methods for treating precious metal ores, and is selected primarily to take advantage of its low capital cost relative to other methods. Thirty-seven different heap leach operations with a total production of 198 […]

Pachuca Tank

pachaca_tank

Pachuca tanks are used for a wide variety of leaching and mixing operations in the minerals industry. Previously, an equation was derived to predict the circulation in a Pachuca tank with full height draft tube risers. This analysis was subsequently verified with data from a large bore air-water flow loop used. However, the equation was based on the assumption that the solids settling velocity was […]

Gold Leaching

Flowsheet

Gold Leaching Process Circuit NO. CY-1 This leach plant shows the continuous counter-current decantation system, in which all the ore is first reduced to a very fine state in the grinding mill-classifier circuit, in a Gold Leaching solution. The slime overflow of the classifier, usually 70%—200 mesh, or finer, is sent to the first thickener, known […]

Gold Cyanidation Process

Methods Used in Concentrating

The gold cyanidation process is the most important method ever developed for extracting gold from its ores. The reasons the widespread acceptance of cyanidation are economic as well as metallurgical. It usually obtains a higher recovery of gold than plate amalgamation and is easier to operate than the chlorine or bromine process. It produces the final product in […]