They most likely used the 62% grade to allow for a common...

They most likely used the 62% grade to allow for a common benchmark across other producers. They have said they are able to produce up to 68% grade, however even if they only produced 62% grade, if they can do so at a profit, this is no bad thing, and still a higher grade than what some DSO operators ship.

We know higher grades result in a higher sale price, but there aren’t many producing 68%+ grades to allow for easy comparisons. Furthermore, it may cost more to produce 68% grade, compared to 62%, however the sale price of 68% is also higher. Shipping/transport and some other costs should remain the same regardless the grade, and it shouldn’t cost that much more to produce a higher grade.

If they include their costs as you’re said they should, it would make it very difficult to compare to others, nor would be be able to easily tell if its a good or bad result.

Furthermore, I expect we will see better numbers once the DFS is released and they have had a chance to test out the NextOre technology. At that point you should have a clear indication of what it will cost.