Kaleen, I agree - 50,000tpa is definitely going to up the sp.
However I wouldnt be using todays Silver price as imo long term silver prices and copper prices will drop back. If anything Im of the view that copper is going to hold a far greater percentage of its gains than silver.
I liked the comments in the Quarterly today that there was some historic production of 224kt of manganese. This has the potential to be as big or bigger than Boseto.