A pipe may contain material from several emplacement phases. Within the phases the material may have been subject to different cooling conditions.
Someone previously described the Snap lake dyke emplacement as having been shot like a bullet into solid granite and creating the crack which it immediately filled. It would probably be safe to say that this was done under great pressure. The nice thing about a closed end narrow dyke of this nature is that it would cool rapidly. It would not be subject to a large stream of hot gas and hotter magma streaming through vapourizing the diamonds, churning the mix, mixing a lot of country rock etc.
In short, the chemistry, the amount of diamonds, the course nature of the diamonds and the high quality of the diamonds indicates that conditions were very good for the preservation of diamonds.
I would not think that it would take a great jump of logic to think that if conditions were good for preservation of diamonds at points A, C, E, G, and I---that conditions would be similiar at B, D, F, and H.
However, having said all of that, the bulk sample and actually mining the deposit could surprise us either way. The question is what are the likely rewards and risks of being in or out. |
