Mining Stock Education · Wednesday, July 15, 2026
Dr. Rob Stevens defines refractory deposits as those where metals are locked in minerals that resist conventional processing methods, potentially making recovery challenging and costly. He notes that gold trapped in fine pyrite or arsenopyrite, or complex copper sulfide/oxide mixes, may require extra, expensive steps like roasting or pressure oxidation, impacting economic feasibility.
“Refractory, uh, refers to metals that are contained in minerals that cannot be processed using conventional methods. Uh, the, uh, chemical structure of the mineral is such that recovering metals out of it, such as copper, uh, or, uh, even gold can be challenging.”
“Uh, and I know, for example, uh, gold often is trapped in pyrite or arsenopyrite, uh, and if that pyrite is fine, and couldn't be, uh, effectively broken up by grinding to liberate and free up that gold, uh, then you may require the addition of a roaster or pressure oxidation, uh, part to your, your processing flow sheet, uh, which adds extra cost and time to to processing.”