There are two parts to the riddle;
1 The intrinsics about tthe ore body. Iron content, foreign metal content and the capital and cash cost of extraction.
2. The assumered market price. The going price was $190 not so long ago and then the price plummeted by more than 50% last August to as low as $88. In recent months the price had been around $118.
Clearly, if the cash cost plus handling plus freight to China is over $100 and the market price is $118, then the iron ore is worth little but at $160 it could be very valuable.
If cash costs and freight to the coast are $60 or less then in a $160 iron ore market the iron ore deposit is very valuable.
The freight cost to Asia should be $15 lower than the Labrador Trough cost
With or without iron ore, the deposit is large, economical to mine and in a perfect location