the material is as you calculated 52.8Mt x 8.3% = 4,382,400...

the material is as you calculated

52.8Mt x 8.3% = 4,382,400 tonnes

of course, 100% of it is not mine-able

say 65% is mineable & recoverable

that is 2.8 million tonnes

at production rate of 100,000tpa, that is a 28 year mine life

the flake size is irrelevant for these calculations, unless there are large quantities of very small flake size

BKT has around 12% very small flake size therefore reduce the material by another 12%

the flake size only determines the quality of the final product & thus the potential profit margin

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