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Message: Coarse gold and the tesoro drill core results

Hi Mikxx, as for your mention of the SH posters and their interpretations of gold processing, I have to say that some do have an agenda, and do try to discredit me. However, time and time again, they seem to only succeed as far as putting their feet in their mouth further. You can blatantly see that their DD is very limited, by the things they post and that they do have a motive to bash the property and try to make it look bad to investors. Professionals know what the property may very well hold, and its a shame that they don,t post and give the investors some professional opinions to counter the nay sayers, making them redundant.

As for the coarse gold, you will see in my post that I touched on that subject and focused on "This this leach pad may have been used for metalurgics, in determining the recovery rate of gold from sulfides and/or disseminated gold within the host rock."

And also you will see where I touched on and distinguished between the coarse gold and the disseminated.

"We were told that most of the gold on the Tesoro was free milling and a nominal rate of return was around 90%, these figures and info arrived from data received from the ore sent to Dynacors mill."

http://agoracom.com/ir/steliasmines/forums/discussion/topics/579068-photo-of-leach-pad-on-tesoro/messages/1816909#message

As for our high grade bulk sampling, this happens as a result of sometimes high grading the vein, or in easier terms, just taking the vein which may be only 15 cm wide. In news releases, you must watch for the words "vein material" "ore" or "development material". When the word vein material is used, it suggests ONLY the vein, and when establishing economics and a mining width, this depends on the width of the vein, and a favourable width of a vein would be approx 1m, IF THERE IS NO GOLD IN THE HOST ROCK. If there is gold in the host rock, this has to be factored in to get an average grade over width, to see if its feasible to extract the ore. Two safe rules of thumb, used to be a grade of 7 g/t or above for a shaft mine, or 3 g/t or above for an open pit. We beat the shaft mine figure of 7 g/t when the company mentioned in one presentation that 1 ounce per ton gold, or ~32 g/t was the average grade of DEVELOPMENT MATERIAL. As for the open pit figure, with the POG so high last year, miners were able to economically extract gold by the open pit method, depending on good gold recovery rates of probably 90% at least and the composition of the ore, ie; sulphide content, of around 0.20 g/t. When there is a high enough grade of by-products in the ore, like copper, this adds to the economics, providing the grade overrides the cost of the seperation process used.

The Tesoro geology is unique in so many ways, although not so unique, but an important characteristic of the Tesoro, is the high grade off shoots of the veins. Add into this mix, mineralized veinlets, mineralized host rock, silicification mineralization, and you are not long seeing the potential of a mine. Its the area that the mineralization is able to expand over and remain a consistent grade above an economical grade, in which creates a mine.

As for you wondering why our drill core results did not seem to portray a sufficient gold grade to match the bulk samples, well they did in the way that drill results usually will, be perhaps 3-6 times less than the actual grade of the deposit. There are several contributors for this reason, one being, you are only getting a small sample, which makes it difficult to get the true average of a ton of the ore in the area the drill hit. You may move the drill one half inch, and hit a high grade nugget, you may move the drill one half inch the other way, and get nothing. When you are taking a bulk sample, you get the average over a linear length and also a width, thats why bulk samples are more representative and reliable in establishing the grade and economics of a deposit. In our case, its not the veins we hit in the drill cores that were of utmost importance, it was all the other mineralized structures that should have been sampled, the granodiorite, alteration, silicious altered zones, shear zones, dykes, etc. Its these structures that tell you if you have a bulk tonnage deposit and the most valuable, perhaps for the Tesoro.

As for this part of your post; " Here is the info from the other company..................................two 1 kg one meter long channel samples, screen fire assay, 0.73g/t and 0.98g/t gold. A 617kg rock sample blasted from the SAME LOCATION, crushed and blended, 2 -10kg sub samples assayed 32.4g/t gold, 88% of gold was recoverable by gravity................................."

You have to be very careful in analysing the above data, and to be frank, its not enough data to really tell you anything. For instance, we are much with the same problem drill cores present when determining a grade. Where there were only 2 sub samples taken, which represented less than 4% of the total sample, this could very easily be biased toward the high side and not a fair representation of the entire sample. The greatest reliability and emphasis here should be put on the former channel samples, these samples give you a better representation of the grade, whereas they are consistent samples along a linear aspect of the mineralization. The two subsamples werwe most likely hand picked and may have even been high grading the ore, which could give a totally false impression of the true average grade of the whole 617kg sample. Not saying this is the case, but with the limited data you presented, thats all that can be derived from that.

The drill results have not been interpreted incorrectly on the Tesoro. If you recall, I put a happy face for one of my posts around the time of the initial drill results. This was because of the multiple veins found in the Canchete area, which equated to more than we thought was there, but corresponded well with the Quantec. If you notice as well, the size of the samples is very small, perhaps smaller than the actual width of the veins in some cases, and this will not give a clear indication of the grade of these veins, if that is the case. Furthermore, there were areas of identified dissemination on the surface, that havent showed up in these drill results yet, which I find very puzzling.It was my impression then from the news release, that the other holes, the ones in Zona Central, which were not too impressive, were only initial results and that these holes would be further tested and assayed, and perhaps focusing on the probable disseminated areas of the core. I don,t wish to get into anymore of this reasoning on this subject, because thats where everything seems to get out of whack and doesn,t make sense to me, and we have been there before anyway.

http://steliasmines.com/?p=1255

Anyways, this is all in my opinion, hope it helps.

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