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 |
