The Brains Trust - 2020, page-1840

Thanks for that reply daveironore.............great work.

yea, i know the basic formula to convert volume to tonnes, but , as you correctly point out ,it is the density of the various rocks that I am having trouble with. i have found some sites on the internet that will give me the answers but they a subscription sites requiring money....Yuk!, well not really, they deserve thier income, but for me it's a one only need.

but I have seen the 2.5 number a few times.

and, of course, my whole exercise is approximations only for my needs, not precision

Thanks again. Owe you a beer (or a cuppa)

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