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Gold/Mining/Energy : Canadian Diamond Play Cafi -- Ignore unavailable to you. Want to Upgrade?

To: VAUGHN who wrote (311)	11/22/2002 5:16:14 PM
From: Diamond Daze	Read Replies (1) \| Respond to of 16206

Hmmmmmmmmmmmmm syd.dem.csiro.au According to microprobe you can.

To: VAUGHN who wrote (311)	11/22/2002 6:08:30 PM
From: 1st.mate	Read Replies (1) \| Respond to of 16206

go to diamond exploration!! on the formentioned site

To: VAUGHN who wrote (311)	11/22/2002 6:24:23 PM
From: teevee	Read Replies (1) \| Respond to of 16206

vaughn, In the case of the TrustMe claims that TeeVee referred to, apparently a few of the G-10's had exceptionally high chrome content and an unusually large number of the pyropes recovered plotted into the G-10 vs G-9 category. In addition, apparently there were a number of eclogitic garnets with good geochemistry recovered. However, no knowledgeable commentator should imply that a mining company's trumpeted high quality geochemistry in any way heralds the probability of Diavik grade pipes! It simply increases the potential that the kimberlite may be economic by virtue of having sampled the diamond stability field, but as you know, there are a myriad of other factors that determine ultimate economic potential. I didn't refer to the TrustMe claims. I believe Letmebe Frank re posted Willp's comments. I do agree that Willp is a knowledgeable commentator. I don't agree that Willp's comments in any way implied that a mining company's trumpeted high quality geochemistry in any way heralds the probability of Diavik grade pipes. Your post essentially reiterates what I have previously stated: good chemistry only indicates that a pipe may be diamondiferous and because diamond content in the upper mantle is heterogeneous, determining grade and size distribution of diamond in any diamond bearing pipe is therefore an empirical process that is costly and time consuming. Another "indicator" worth paying attention to is the percentage of mantle xenoliths in a kimberlite. Any juicy rumors from the YK geoscience forum? cheers, teevee

To: VAUGHN who wrote (311)	11/22/2002 6:38:31 PM
From: WillP	Read Replies (4) \| Respond to of 16206

VAUGHN: I see a few others have weighed in on this issue, but I'm going to say a few things as well. ;-) You say, To the best of my knowledge, there is no correlation between kimberlite grade and most geochemistry, including the quantity of G-10 pyropes, the quality of G-10 pyropes, or any other standard suite indicator mineral whether it be, Chromite, Illmenite, Chrome Diopside, Eclogitic Garnet, Olivine, etc., etc. There is a correlation, but it is very small, in my opinion. The only reason there is a correlation is the fact that poor chemistry does not bode well for diamonds, and great chemistry is a good sign that a kimberlite will be diamondiferous. That has very little to do with grade, of course. So Diavik/Aber's pipes may or may not have excellent geochemistry, but that has only little to do with their high grades. Actually, Diavik had only "decent" G-10 garnet numbers, compared with say, Freightrain, with its clearly vastly inferior grade, and with some of the Mano River kimberlites that had a nearly nonexistent grade. You said, However, how thoroughly the kimberlite scoured the diamond stability field, to the best of my knowledge, cannot be determined by geochemistry. Or, if there were any diamonds there to be scoured. You say, However, no knowledgeable commentator should imply that a mining company's trumpeted high quality geochemistry in any way heralds the probability of Diavik grade pipes! It simply increases the potential that the kimberlite may be economic by virtue of having sampled the diamond stability field, but as you know, there are a myriad of other factors that determine ultimate economic potential. Hmmm. I'm not sure which, if any, "knowledgeable commentator" you are referring to, but I must agree that it would be incorrect to make such an implication. I have not come across any such assertions in my travels however, outside of some promoters who hope investors will make the assumption on their own. I have mentioned G10s in a few articles, and as the data shows, many kimberlites have G10 populations clearly superior to that of Diavik, with much poorer or nonexistent grades. That should be a real caution against assuming too much from the available data. Having said all that, I would rather my kimberlites had great geochemistry. Just for the record. ;-) Regards WillP

To: VAUGHN who wrote (311)	12/8/2002 10:45:50 PM
From: russet	Respond to of 16206

http://www.siliconinvestor.com/readmsg.aspx?msgid=18314068 I had followed GMD in the past. Some of the personnel on the promotion side were I believe hit by the BCSC. (Farell (sp?)) They also had some gold properties up north. This is not to say that the quality of their properties in and of itself was bad. The gold thing they had was good, but gold is very hard to develop. They had tried to expand the width and I was of the opinion that it would not go that way to any significant tonnage. That point so far remains not proven either way. The Royce property may or may not have merit. I have not seen the data. I at one time looked at Dupuis' data on his diamond properties at least in Cypango, which is now defunct, but I found his reportage was really short on the necessary details to judge. Of course he would have said trust me, and it's proprietary, which it is, I guess. But I find that all diamond chemistry reportage is really weak in Canadian diamonds. This is because for the most part they just don't know what good chemistry is. (And they know the investor doesn't either) The data is lacking and the expertise is too. I believe a lot of people believe Gurney out of hand, but do not give sufficient credit to Griffin and Ryan's nickel thermometry nor Sobolev sr.. or jr. as to their obviously working data. The tendency in the industry to BS the data, and to leap on foggy bandwagons is high. What to ask the diamond companies is to see: 1. what the nickel, chrome, calcium, and aluminum content of 100 of ALL of their garnets are. Whether sodic-eclogitic or pyrope. by both PROTON and ELECTRON microprobe. Proton probe is done on nickel and zinc. Electron probe is done on calcium chromium, and aluminum. Zinc is useful but we won't talk about that. I would suggest figures from Griffin and Ryan at CRA in Australia, SasK. Reseach Council, Guelph University, B. McClanaghan's lab, Kaderjavtseva at Moscow State, V. Tchigonov's lab, and Montan University, Austria can be relied on. 2. what the chrome and calcium of the 25 of their high chrome pyropes are. 3. what the chrome and calcium content of their chrome diallage (low chrome pyroxene) is. Most companies do not know how to get their data done nor how to interpret it afterwards. They do not have sufficient data in nickel temperature curves from proton probe for one thing. They also do not know how many pyrope to test from or percentages of what elements in how many pyrope are significant in Canada. You need to get a nickel-temperature curve on 100 garnets by nickel-thermometry/chrome barometry by proton probe. This data is hard to interpret and needs to be compared to curves in producing pipes. The theory maintains that the higher the temperature and the more mono-peak the curve is, the better up to a point. Proton probe of nickel is rarely wrong in terms of absolute grade, and explains the zero pipe to be just that. (the famous high-pyrope pipe that was barren of diamonds in SA. ) The method is cheaper and faster than electroprobe, and can be used on ALL garnets, not just pyrope, so it works on lamproites, low pyrope Orangeites, Yakuts basaltic kimberlites, rocks of the Winter Sea field, lamprophyres and eclogitic kimberlites with sodic garnets. ******* You should also use the Yakuts platform electron microprobe data for subcalcic garnets (NOT the Gurney diamond stability field data, which is similar) by Sobolev's criteria for diamond mines by electron probe of the diallage and pyrope. This is sometimes called the diamond stability field. It is not purely that, but more a statistical averaging of the chrome calcium ratios of pyrope found in Russian diamond producers. It says that with a 13 percent population or greater of pyropoe containing more than 5% chrome and less than 2.6% calcium, you have a statistical certainty of being in an economic diamond rock. This simple statistic has been totally lost on Canadian diamond explorationists. The minimum population size is 100 garnets for a good sample. Bad sampling of many Kirkland Lake pipes, particularly the A-4, which contained, obviously by visual inspection, MANY high chrome pryopes (you can tell by the depth of the purple colour and non-facetedness)-- leaves the potential of that large extremely-diamondiferous-by-hit rate field a mystery. All of this data is statistical analysis of the eutectic of the garnet, -- its composition which gives a pressure and temperature of crystal formation. It correlates highly with both diamond stability at pressure and temperature of formation -and- the statistical presence of diamonds in mines. These are two different factors, as the oxygen fugacity of the ascending pipe is also important. (to diamond survivability on transport from depth of formation. ) It is also important to realize that macro and micro diamond content ratios have NOT been established as being related to the economics of producers. All diamonds it appears were formed about 3.8 billion years ago, at depths from 90 to 180 miles beneath the surface. They were then transported to surface in stable basin areas NEARER THE EDGES of these basins (not the centres!) from one billion to 16 million years ago in near synchronous world-wide explosive volcanic events. The explosive volcanoes came in in stages but were uniformly or near-uniformly explosive cold-ash breccias exiting the pipes at up to supersonic speeds, to spew sometimes 6 kilometres in the air. These volcanoes formed distinctive rock textures, called diatremic, which is a porphyritic breccia. (It looks just like road concrete or pavement but more colourful. The crystals in true kimberlite can be deeply coloured. The ground mass varies from deep blue to pale grey to pale yellow.) The pipes formed low fall-back cones and wide depressions whose ridges quickly erode. The rock is characterized by it tendency to decrepitate in sunlight. The South africans used to just crush the mine rock and let it corrode in a few months on the surface to release the diamonds. EC<:-}