May I add that using 0.5% cut off grade for nickel is just fine IF...
...it was just nickel in the ore because that amount would be approx. the break even level on processing and overhead.

HOWEVER, we have fairly large amounts of 3 other metals whereby any one pays for processing and another for overhead leaving the 3rd and the nickel as if for free.

Just an example of how some are unable to see what is really there.

All in my opinion.