RE:RE:RE:NEWS- Gold Standard Reports Positive Metallurgical TestJust a little info with regards to the reason the market may not like this most recent press release with regards to the Met. The recovery on the 10 mesh is not all that good. 10 mesh equates to 2 millimeter size material. 200 mesh is equal to .074mm. 200 is what you can basically crush then grind a rock down to without going to extreme methods of pulverizing. Generally, when you have an oxide heap leach deposit, you want to handle the material as little as possible. This means placing ore on the leach pad in what is called Run-of-mine. ROM is what the rock appears after blasting and being loaded onto a truck and then deposited to the leach pads. At this size we are talking 6 inch on up to several feet. They may design the blast to keep it smaller etc, but common size is in that range (over simplified). On some mine projects they will crush the ore to smaller sizes, but this adds huge cost to the leach plan. When you start talking about crushing or pulverizing ore to 200 mesh, it is going to go through an actual mill that would include Carbon in Leach circuits, ball mills, etc. This type of operation requires huge capital and is only done on much higher grade deposits then the proposed Pinion project. The reality of this is in no way could you ever afford to ever crush even down to 10 mesh and put on a leach pad. Several things “MOST” likely would happen if you went this small. Cost would go through the roof to crush this small (thus changing the dynamics of the resource and cut off grades) and it is highly likely that the leach pad would not function the way it should because that small of material tends to eventually plug up and not allow the cyanide to actually reach all the ore placed.
There are multiple ways in which to deal with the issues, but it adds significant cost. If you want to kind of get an idea as to the recovery if you go with certain crush size (mesh), plot the two numbers given and draw a line from that proportionate to recovery on Y axis and Mesh size on the horizontal. Most Carlin type deposit are crushed to somewhere around 75mm.
A good read provided below:
https://www.kcareno.com/pdfs/mpd_heap_leach_desn_and_practice_07apr02.pdf Leach pad technology is much more complicated than most people realize. I can provide many examples of massive failures due to poor leach pad design or short cuts taken. (Look at Midway Pan Project, Look into the Equinox copper project in NV… and the list goes on). The amount of clay in a system can really mess with leach pad characteristics.
It would appear that this deposit though oxide, has some silica encapsulation issues. This same issue was present on Newmont’s Emigrant mine. It ended up working but this issue held the project up for numerous years while waiting for the right gold price and some innovative leach pad techniques to extract the ore that was cost effective.
I am not saying that they will not be able to extract the gold, but there is a huge technical side to this. I am not an expert, I just understand some of the issues associated with low gold recoveries and crushed size rock. GSV has one of the best metallurgist in the world consulting on this and that is a very good thing. The end of the story will be when they get the next set of results for the column leach and then apply the results to a Prefeasibility or feasibility study. Think in turns of the original 43-101 and what happens to the grade or total ounces with much smaller recoveries applied. Also look for the company to run some Bulk samples…
All this is just my opinion, and any investor that looks at this company should do there own DD, call the company and dig into what these results may actually mean. FWIW, I am and have friend and family who are investors in GSV.