But for every down, there has been an up and generally an overall general and sustained improvement. We have this huge ore body with all its variables and we’ve been fine tuning our concentrator to deal with all its irregularities. And we believe we’re about 98% there. Now that we believe we finally figured out the guts of our SAG Mill and its mechanisms, we are now aggressively focusing on our mine to mill optimization initiatives.
As you can see from about the third week of June, at the right side of the chart when we began working on our mine to mill optimization plans, along with new mill liners and ports incorporating all of that, we’ve learned over the past year we’ve moved back up towards 2,450 tons per hour. Some of you may say that we were there at mid-December, early February and we were in terms of mill tonnage, but we were not entirely sure why we were getting the throughput we were. Was it the pit or the concentrator?
While we found out shortly thereafter our enthusiasm at hitting design targets was more about ore characteristics overall than mechanical modifications. We felt we had that under control at year-end but different rock type and other operational issues pushed us back. And even though we cut larger pebble ports at the end of May, because we were still dealing with ore that was blasted two or three months prior, we did not see immediate results.
In slide two, you can see that the 3.75 inch ball that we are now rejecting. You can see that in the circle, the yellow circle on the right side of the picture, but an important note is that re-circulating load that’s coming off the top of the screen decks. That is a very good indication of the performance of the mill. These 3.75 inch balls are both 70% spent so now with the discharge ports that we manually cut into our grates, we are now beginning to see the impact on those changes. The mill is more efficient and that is certainly evident in the re-circulating load.Read the rest of this transcript for free on seekingalpha.com