Hi BLOG, please don't take offence to any of the following...

Hi BLOG, please don't take offence to any of the following comments as I wish to be educated, I have read rizzla comments and excuse my ignorance but don't understand " huge tonnage " and the comment, "doubt there are many IOGC deposits of the size getting off the ground " (is the problem IOCG or its size?).
The grade does not appear to be low to me ( complete amateur) Research of the top ten mines in 2014 are as follows
1 Escondido- open pit 26.2Bt @ 0.523% Cu.
2 Collahuasi- open pit 9.96 Bt @ 0.8% Cu.
3 El Teniente- underground 2.02 Bt @0.86% Cu
4 KGHM Operations- underground 265mt @ 1.66% Cu
5 Los Broncos- open pit 2.06Bt @ 0.51% Cu
6 Los Pelambres-open pit 1.4Bt @ 0.59% Cu
7 Moronci-open pit 9.7 Bt @ 0.25% Cu
8 Antamina-open pit 0.647Bt @ 0.94% Cu
9 Chuquicamata-open cut 0.9Bt @ 0.83% Cu
Will go underground in 2018 to access 1.7Bt @0.7% Cu
10 Radomiro Tomic-open cut 2.7Bt @0.47%
Underground it is suggested, needs 3x the copper% to make it viable.