cmr igv 118 dollars per share 3 march 2008, page-9

Relying on IGV is very risky. Basing it on current metal prices even more so! Its not out of the ground, processed and sold yet, and by the time it is, could have dropped considerably in value. Also producing concentrates which are worth between 60-90% of processed metals.
Personally ignore most metal inventories described as inferred and if they don’t have a mining lease over them.
Also the tonnages mentioned in the chart do not include losses from waste and processing, quite easily 20%.

Applying these factors, the IGV is reduced to less than 6 bil, then half for Hunan, 15% royalties and then lets not mention the ATO!

Apart from that, Tom on the wing is probably the most realistic in his method for valuing SP.