Hi Gus.
Take another look at Core Mining's Resource figures again.
All Inferred resource.
It is 690 Mt at 58%Fe at 45.5%Fe cut off.*** OR 580 Mt at 60%Fe at 49%Fe cut off. Not 690 plus 580 Million tonnes as you are saying.
Back to the research page again I suppose.
Regards
Westcott.