Am I on the right track ? - ATU just announced it has settled...

Am I on the right track ? -
ATU just announced it has settled the $800,000 balance by promising a 0.5% royalty on FOB shipments for 10 years @ 0.5% and then ongoping at 0.1%.
Lets say long term average FOB is $170 per ton or $0.85/ton x 3 million tons pa = $2,550,000 x 10 years. = $25.55m (ignoring the ongoing royalty @ 0.1% in this quik calculation)
If this is correct ..... it doesn't sound like a good deal to me ...... but I am but a humble shareholder, what would I know. Is this calculation any where near right ?