CJR

I never checked your numbers so I cannot vouch for them but you only calculated the cubic meters. In order to calculate tonnage you would have to multiply by the specific gravity. In this case I think it would be somewhere in the vicinity of 2.8. So if we assume your calculations are correct then we would have to multiply your 25,000,000 by 2.8 which would give you 70,000,000 tonnes. I stand to be corrected.

cheers

killick