processing, page-4

To get the maximum benefit from the trial mining, there should be three estimates for the gold grade being fed into the plant. The first would be based on the geological model (resource model), the second based on grade control during mining and the third, the assay from feed samples. When the mill has been cleaned out and a full reconciliation carried out, the actual grades can then be calculated. It is this grade and this one alone that is accurate and should be used to try to determine why the others varied (if they in fact did). Unless I have missed something, we have not seen the first two grade estimates and to me, these are the most important, particularly the estimate based on the resource model as this is what will be used for future predictions.
I have said it before and will repeat myself, getting a much higher grade than predicted is just as problematic as getting one much lower. A good example of is was during my time at the Super Pit in Kalgoorlie, we had a 6 months reconciliation of 160% on contained gold. Most people thought this was a great result. However, think about the consequences. If the accuracy of the model was due to the validity of the modelling process, a result of -60% could just as easily result (and no one would accept this as a good result). The other consequence (and one more likely to apply to ABU) is that the gold is there and all of the design work done is sub optimal and will require considerable re-work. In the KCGM case, more houses needed to be purchased and demolished, roads needed to be re-re-aligned and considerable redesign required when it was found that the gold was there. This is why reconciliations are a fundamental part of operations.
As to the gold in circuit, I think that 1,000 ounces appears high but not impossible. 1,000 ounces would equate to around .0016 cubic meters or around 115mm (around 4&1/2 inches in the old money) cubed - easy to hide behind mill liners, in sumps and pumps etc.
As for the reason why it took so long to treat the ore, look at the plant. It is a bit agricultural but it fits with the current strategy of self funding. While I agree with the concept, I truly believe that once the trial has been completed and analysed, a re-think on processing strategy is needed.
My opinions only