It is definitely true that there are a lot more factors to...

It is definitely true that there are a lot more factors to valuing diamond concessions. The biggest being that with other commodities, you have a set price of how much the commodity is worth per unit of measure. It is not so with diamonds, factors such as diamond size matter greatly. It is precisely this factor which is why Lulo is one of the most prospective concessions in the world, as was shown today.

Are there ANY other examples of diamond concessions which have shed such a large average carat size and such a large amount of 5ct+ diamonds in such a short period?