RE:RE:RE:European Gold Forumpetersburggray,
So I am happy that Darren finally got the "gold bug"! Maybe now that he is finished building his ZINC empire, he can start building a real precious metals company that has some serious silver and gold production. I thought that his European Gold Forum presentation was very good, but IMHO it is going to take some time to prove up the 120 zone into a resource.
If I remember correctly, the production plant is permitted for 3000 tpd, and the San Rafael lead-zinc flotation circuits take up 1800 tpd of that permitted capacity, so they could add the ball mill that was already purchased by Scorpio Mining and run a 1000 tpd copper flotation circuit.
But if the drilling results are showing some drill holes grading 7 g/t, then the question is, how much of that gold is gravity recoverable? Second question, how much of the copper silver and gold in the upper 200 meters is OXIDE mineralization, not amenable to flotation? So if there is significant gold and silver in that top layer, then it may be worthwhile to build and install a 3000 tpd process plant with a SAG mill, ball mill, fully hydrocyclone arrays, gravity circuit, flotation circuit, and CIL. Plus add gold and silver dore production capability.
The following background is from the San Rafael 43-101 report:
13.3.3 Zone 120 and 120-Main Overlap Zone Composite Batch Flotation Test
A single batch flotation test was conducted on each of the Zone 120 composite and the Zone 120 mixed sulfide (Main/120 overlap) composite. Results from the Zone 120 composite flotation test showed higher than expected weight pulls of 23.4% to the rougher concentrate and 11.8% to the cleaner concentrate. The cleaner concentrate produced from the Zone 120 composite was 11.8% of the feed weight, assayed 1.53 g Au/t, 1,400 g Ag/t and 4.45% Cu, and represented gold, silver and copper recoveries of 70%, 81% and 86%, respectively.
Batch flotation test results showed that the Zone 120 mixed (Main/120 overlap) sulfide composite did not respond particularly well to the sequential lead-zinc flotation procedure optimized earlier for the San Rafael Main Zone composite. The Zone 120 mixed (Main/120 overlap) sulfide composite contained only 0.26% Pb, probably making production of a high-grade lead concentrate difficult. A substantial portion of the contained zinc (32% of total Zn) reported to the lead concentrates, limiting the zinc recovered in the zinc concentrate.
Further flotation-optimization testing was conducted at McClelland in 2008 on the same two composites and did not lead to a significant improvement in flotation response. The results indicated that additional testing is required to prove metals from Zone 120 can be recovered in a saleable concentrate.
Additional testing of Main/120 overlap sulfide material containing a more representative lead content is also warranted.
The Zone 120 mineralization occurs not as a single horizon, but as multiple bedding- and intrusivecontact-related mineralized horizons. As currently defined, the Zone 120 mineralization occurs within a rock volume that is about 500m long, 250m wide, and extends to a depth of about 350m below the surface. The Zone 120 geologic setting and mineralogy are similar to the nearby El Cajn deposit in that the silver-copper-gold mineralization occurs primarily within weakly sulfide-bearing (<6% by volume) pyroxene skarn that is spatially and possibly genetically related to diorite intrusive sills and dikes.
The Zone 120 occurs primarily below the up-dip extension of the Main Zone zinc- and lead-rich massive sulfide, though both styles of mineralization do overlap in the near-surface. Below the massive sulfide, the Zone 120 mineralization occurs within moderately to strongly skarn-altered limestone. Near the surface, within and above the Main Zone, the Zone 120 mineralization occurs within weakly to moderately skarn-altered volcanic rocks. The Zone 120 skarn mineralization generally strikes 330°, and below the massive sulfide, the bedding-related mineralization dips steeply to the northeast at about 50°, reflecting the orientation of the host limestone formation and also the numerous sill-like dioritic intrusive
bodies.
The Upper Zone mineralization occurs within the volcanic rocks about 50m to 100m stratigraphically above, and sub-parallel to, the up-dip extension of the Main Zone massive sulfide. The primary mineralized horizon within the Upper Zone is localized along bedding or possibly a sub-horizontal, bedding-parallel structure. The mineralized horizon can be up to 15m thick but often is about 5m thick. Within localized areas, multiple “stacked” mineralized horizons do occur, often spatially related to intrusive dikes, which cut through all rock types and extend to the topographic surface. Upper Zone mineralization is dominantly silver and gold, with decreased sulfide and base metal contents.