Ann: Highest Diamond Recoveries From Lulo Kimberlite Bulk Sample, page-73

Not sure why you are first calculating the radius. You could simply have done V=A*h=35000*300. It's 10.5 Mcbm not 3.509, not sure how you come to this figure because your formula is right although a bit complex. So also the overall carat amount is 262.500 not 87,724. Assuming 1.000USD per ct (which would mean that there are also specials in there), this is roughly 250MUSD in diamonds. Not a big deal but might be commercialy viable although for sure not being a cash cow. For sure not the source of all the alluvials but maybe worth to develop it. Let's see and wait for the final results. Definitly not a game changer in my opinion but maybe nice add-on.