Previously, I have argued that the technical failure of the...

Previously, I have argued that the technical failure of the Lance project is in part due to the complete lack of relevant metallurgical test work through all phases of the project, to inform the process design. I have also said that technical issues were identified/evident during historic testwork but were seemingly ignored or went unnoticed. Is it any wonder that the plant performed so poorly, as confirmed by the PEN graph below?



PEN predicted 80% recovery for the alkaline route. They only achieved 48%. They are predicting 90% recovery for the acid route. So, expect 54%.

The low pH processing feasibility study confirms once again that PEN doesn’t pay enough attention to the metallurgy/chemistry. To table a feasibility study and financial model that is informed by only 6 agitation leach tests and 2 column leach tests is scandalous in my opinion. Why is it that many thousands of metres are to be drilled to inform resource/reserve estimates, yet crucial (project making) metallurgy can be confirmed by only a handful of tests? Putting that question aside, how can PEN expect any investor to have confidence that they have it right this time round based on a fistful of lab tests? Based on historical performance, I would have zero confidence that they have got this process design right. Ditto for the hydraulic performance of the ore zone under the new, low pH conditions. At the very least, technical diligence demands a field leach trial be performed. Several field leach trials at different locations are indicated based on past performance. Why isn’t this been done?

A key point for low pH success is the issue of gypsum formation in the ore zone. Carbonate + sulphuric acid = gypsum. Gypsum readily precipitates from solution and can potentially plug the ore zone. Uranium leaching drops as the lixiviant is unable to contact all areas of uranium mineralisation. It’s obvious that carbonate content is at least as important as uranium content when making statements about potential about gypsum formation. Yet the entire carbonate/gypsum debate is put to bed by analysis of 14 drill cores across Ross, Kendrick and Barber, which together span an area > 100 square kilometres. Astounding. This is a fatal flaw for me.