The reserve statement doesn't tell me exactly what it was they...

The reserve statement doesn't tell me exactly what it was they impaired. If a good chunk at the time was pre-strip you ain't ever getting that back as they would've minede the relevant amount. Unless they paid for the reserves from a third party they wouldn't have had a value on the balance sheet. I agree they are worth a lot in a dcf, but that's a business valuation not an impairment reversal. There would I expect be some items that on a depreciated historical cost would have value that could be reversed above the current carrying value, but I don't believe that number would be as big as suggested.