To: mineman who wrote (12948 ) 1/20/1999 11:53:00 PM From: Andrew Respond to of 26850
I think this kills the salting theory. This Dr McCallum has put his stamp of approval on the diamond sample. From the most recent News Release. Diamond Study The parcel of diamonds recovered from the two 100 tonne kimberlite samples obtained from the NW dyke comprises 1,387 diamonds. A study of 1,291 diamonds from this parcel was undertaken by Dr. Malcolm E. McCallum, a recognized international expert with considerable experience in this field. The remaining 96 diamonds that were not studied in detail represent the smallest screen-size of diamonds recovered. Because plant recovery in this small size range is inefficient, these diamonds were considered to be unrepresentative of the size class and were omitted from the study. Although the small size of this diamond parcel precludes rigorous statistical treatment, Dr. McCallum considers that the observed distribution of the physical properties is statistically relevant. The main conclusions of his report are as follows: The various physical characteristics exhibited by the three large gem diamonds (10.82, 8.42, and 6.04 carats) recovered from the kimberlite are completely consistent with those observed in smaller stones from all size fractions. There is a strong correlation of morphological characteristics between diamonds recovered from each of the two sample sites. The number of large stones recovered from this sample is unusual but not unprecedented. Based on the high concentration of large diamond fragments in the +9 and +11 size fractions, as well as evaluation of size-frequency distribution curves, preferential breakage of larger, poorer quality stones appears likely to have occurred either by late magmatic or induced processes. Dr. McCallum subsequently has commented that some of the overgrowth features present on many diamonds in this population have not been reported from other localities in NWT and may provide a unique signature for diamond parcels from the NW dyke at Snap Lake. Winspear notes that kimberlite of the NW dyke is also unusual in its intrusive form and compositional characteristics of its indicator minerals.