Is enami at qb2 a working interest too? 

No, they have a 10% non-funding interest. All of the capital funding to build QB2 is paid by Teck and Sumitomo.

how is the financing clause worth $50 million? Can you explain

Teck agreed to pay the first $ 60 million of pre-production costs. We can claim 25% of that amount as real value to us, or $ 15 million. They've spent $ 20 mil so far, so that leaves $ 40 mil left and $ 10 mil value to us. Then there's the 2 milestone payments of $ 20 mil, which gives a total of $ 50 mil of value in the JV that we would claim in addition to the 25 % of the metal in ground, should we sell our portion of SC.