Tomato, Author: teevee -- Date:1999-02-12 00:24:35 Subject: Are the 3 big stones a fluke?
WillP, You have been busy posting, and good posts they have been. I would like to address the notions of whether or not the big stones should be included or excluded in the average value per carat of $301.00 as reported by WSP, and whether or not we could expect more of the same in a bigger sample, but from a "classical" rather than a statistical perspective. My methods may not be as rigorous as yours, however, I believe they are equally as valid because they are based on empirical experience....the stones are there. As it is late, I may ramble on for awhile as well. I hope you enjoy the story. First of all, the diamond content of the upper mantle is not homogeneous. What this means is that even if transport conditions via a pipe or dyke are ideal for diamond preservation etc., regardless of how good the indicator mineral chemistry is, or any other consideration, diamond content and grade can only be determined empirically by incrimental sampling. Second, diamond size and the value of diamonds in kimberlites (type I and II) has been recognised to be distributed in a log-normal fashion. What this means is that in economically viable hardrock diamond mines, perhaps 4% to 10% of the diamond recovered is responsible for 90% of the value. Large, gem diamond is afterall the objective of the "hunt" and when found, they are never thrown out. Why would we do so here? By Comparison to a known dyke occurence of type II kimberlite(the Bellsbanke mine in South Africa), one can see that about 4.4% of total carat weight recovered is represented by diamonds 10 carats in size and larger at Snap Lake as well. I hardly see anything unusual or exceptional about the presence of the larger stones found in Winspears two 100 tonne samples. I do however suspect the 1-5 carat size range is under represented due to under sampling. An interesting and important aspect of Snap Lake is that the Orangeite(type II kimberlite) is not serpentinized, and for the most part is not contaminated by country rock(as an aside, no serpentinization means no or low clay content which is positive for diamond recoveries in a plant-I have heard that clay is a problem at the Ekati mine plant). If we decide to interpret the rotating dip direction of the dykes as indictative of as hypabyssal cone sheet(if it looks like a cone sheet, call it a cone sheet), this infers through the process of cone sheet emplacement(less volitile magma and also comparatively less phreatomagmatic), not only huge tonnage, but also uniform composition and diamond content (also big diamonds uniformly occuring throughout the cone sheet-but with less frequency of course). This is now supported by the reasonably consistant microdiamond counts from samples collected from the east, south, and west edges of the cone sheet. Interestingly, in contrast to type I kimberlites, this "diamondiferous dunite" exhibits almost no dilution and almost no mixing with and from country rock resulting in low variation in grade(as now also evidenced by CF results). This should also result in comparatively less breakage of diamond than in a pipe... There have been reports of some of the diamond being compared to Russian white diamond. This is a reference to diamond from the now closed Mir mine. One aspect of this which I find interesting, is that the chemistry of silicates from Snap Lake suggests depths of origin from 320-350 kilometers versus 200-220 kilometers depth at Ekati and diavik. The depth of origin for silicates from Mir are also deep seated from depths over 300 kilometers. This is important information which IMO, tells us we can expect overall higher valuations for Snap Lake diamond (whiter color and fewer, if any inclusions). As a historical aside, you should know that the Russian White diamond from the Mir pipe was a big headache for DeBeers from the late fifties to just as few years ago. It forced them to change their grading system because they could not match the whiteness of the Mir diamond. In Canada, Birks was Black listed from CSO sites for buying Russian diamond. Here is my best guess as to what I expect for certain stone sizes, based on my calculations on the back of an envelope, from the 6000 tonne bulk sample: 27 ten carat stones; 3 thirty carat stones and one (two if they are really lucky) 100 carat stone. Let me know what your "guess" is for these stone sizes so we can compare after the results come out. By the way, gem quality diamond of this size comonly averages about $US5000 per carat or more, so....4 diamonds totaling 190 carats (1x100 carat stone, 3x30 carat stones) could be worth $950,000.00, or could add about $160.00 per tonne value. 27x10 carat stones averaging $2000.00 per carat could add about another $90.00 per tonne. If the rest adds an average of $90.00 per tonne , we could end up at $US340.00 per tonne. Hmmmmm...seems reasonable to me..... regards, teevee
Top Reply
Author: WillP -- Date:1999-02-12 08:05:27 Subject: Ahh Yes, Well...
You've been talking to Nick Pokhilenko, haven't you? :-)
Now there's one passionate fellow.
You're speaking to the readers, not to me. I understand that. For the record, and for the readers, I will largely confirm what you say. Or more correctly...
#1. Your basic words are confirmable from the literature.
#2. Discussions with the players at Winspear would strongly lead one in that particular direction. (Not that counts for anything necessarily...every two bit VSE/ASE and most TSE stocks have their unabashed hypesters, after all.)
#3. I agree with your basic conclusions. However...one must still, at this stage of the project, remember that 'hope' is still a synonym for 'conclusion'.
Once again, I will remind everyone of Gren Thomas' casual remarks about coffee cans and shot glasses, this time with a bit of math:
There were 12,800 carats recovered from A154-South. That's 2.56 kg...roughly equivalent to 730 grams of water. Given air space, etc...might nicely fill a one litre can. Now those diamonds were valued at $806,000 US. Go now, if you will, to a shotglass...containing possibly 70 ml of water...or 50 if we allow for air space. Then again we can heap diamonds at the top if we fill it to overflowing...so we'll remain at 70 ml.
Now 70 divided by 730 is just under 10% of the total weight. Thomas said that that accounted for 70% of the value of Aber's diamonds.
I contend, as do you, that such distributions are normal in the course of events. Or more precisely...lognormal. :-)
You ask for my 'guesses'. OK. Fair question. I note you didn't specify gems...so that makes it easy:
Stones greater than 9.99 carats .... 34
Stones greater than 29.99 carats .... 5
Stones greater than 99.99 carats .... 0.5
As to gem quality...of the quality found in the bulk...don't know. I used 25% in the all or nothing approach. As pure optimists like yourself would point out...this flies in the face of reality. Of course...I've pointed that out myself before.
As far as per carat prices go...your quoted $5000 value is...umm...fair. The price does keep escalating with larger stone weights.
I doubt if we well ever get the chance to verify however. Results from caustic fusion are pretty open...and mini-bulk samples are fairly well disclosed. A bulk sample will be much more guarded. Revealing results that *are* statistically relevant will, after all, spill the beans.
I'd like to take one last crack at this:
The release of materially pertinent information in a timely and orderly fashion is mandated. The release of additional information is not.
Once you hit the send button on a news release...everyone has it. I'd like to think that additional information in my hands is more meaningful than it is in the hands of your typical day-trader. I'd be unrealistic to think that someone at, say DeBeers, knows less than I.
The average..err..guy can't draw logically correct conclusions from CF data. That's obvious by the crash-and-burns exhibited by many other diamond plays...is it not?
I can.
It would be logical and reasonable to assume that DeBeers et. al. REALLY can. :-)
From a guy who is long...very long...and has been for years...I'd hate to have it ripped from under me for less than fair value.
But enough...I seem to be losing that battle at any rate. (Though it's still up to WSP/ABZ what gets released...not the sentiment of SW/SI/SH, nor the beliefs of JK/BB, etc. :-)
In closing....
Are the three fine gems a fluke?
Don't know.
I do know that you bet against persistence or reality at your peril.
On the other side I also know if things are too good to be true...they usually are.
Then again:
"Once is happenstance...twice is coincidence...thrice is enemy action." - James Bond.
Nice hearing from ya!
SlavaP |