Effect of Grind Size on Gold Recovery
Your intuition along with common wisdom will have you believe the Effect of Grind Size on Gold Recovery is always uni-directional or proportional. Truth is it really depends on what your mineralogy tells you and what the effective gold grain liberation size is. If you are already finer than needed, going finer yet will not help. […]
Diagnostic Gold Leach Testing
A Gold Diagnostic Leach Test is used to evaluate the distribution or deportment of gold in various minerals is determined by a series of selective leaches, usually by increasingly stronger oxidative acid leaches. Between each stage, cyanide leaching is used to extract the released gold. In this study a total of ten analysis stages were carried out for the […]
Arsenopyrite Gold Recovery
Having some arsenopyrite in your gold ore sample does not insure a full refractory gold processes is needed for recovery. The presence of arsenopyrite and heavy sulphides just tells a component of fraction of the gold extraction process might have a refractory response. This post is no handbook on procedure for treating sulphide ores for maximum arsenopyrite gold recovery, […]
Gold in Arsenopyrite
As case study for the processing of an ore with a refractory component of visible and invisible Gold associated in and with Arsenopyrite had a gold content in the feed ranged from about 1.0 g/tonne to about 8.7 g/tonne depending on lithology. There was some difficulty in measuring the feed gold content due to the presence of coarse gold in […]
Gold Chlorination Process by Miller
Miller’s Gold Chlorination process was introduced by F.B. Miller. The refining process employs chlorine gas, which passed into molten gold covered with a layer of borax and silica, and reacts with most of metals present in the molten charge. Platinum group metals do not react. Basically, gold is slightly attacked in the first moments and […]
Column Leaching Procedure
1) For better Column Leaching, Agglomerate ore if required. The procedure is to cure for recommended time period. During this time the ore should be kept damp via a wet cloth spread over it. 2) Load ore into the column. This should be done with the column on an angle, and the ore poured gently in to […]
Cyanide Bottle Roll Leach Test – Leaching Procedures
List Equipment Required to Perform of a Standard Bottle Leach Test Winchester bottles, with tops Plastic tape to seal tops of bottles Flexible air lines for possible aeration requirements Magnetic or mechanical stirrer for agitation Timer, pH meter, thermometer and weighing device Leachants, i.e. acid, alkaline or neutral solutions, or specific solutions Filter: vacuum or […]
Sulphide Leaching
Methods of leaching sulphide ores can be: in absence of oxidizing agents in presence of oxidizing agents Bacterial leaching Absence of oxidizing agents Acid leaching: Dilute acids dissolve some metal sulphides with liberation of H2S, e.g. ZnS + 2H+ ^ Zn2+ + H2S Three types of sulphides can be encountered. Completely soluble sulphides: Zns, CoS, […]
Cassiterite & Wolfram and Scheelite Leaching – Oxide
Natural cassiterite on account of its crystalline nature is extremely difficult to dissolve in acids or alkalies. Artificial cassiterite on the other hand is amorphous and soluble in acids. Cassiterite can easily be reduced however to Sn, which soluble in acids or alkalies. Pressure leaching has been applied to cassiterite concentrates using Na2S and NaOH […]
Gold Metallurgy and Leaching Process
Leaching, often gold, is the process of extracting a soluble constituent from a solid by means of a solvent. In extractive metallurgy, of gold, it is the process of dissolving a certain mineral (or minerals) from an ore or a concentrate, or dissolving certain constituents from materials such as a calcines, mattes, scrap alloys, anodic slimes, […]