Ann: $40M Underwritten Placement to Fully Fund Century Restart, page-84

Clearly you haven’t read any of the company reports or independent SRK so I will break this down for you as to why the tailings is still a current orebody capable of being extracted with the same treatment plant.

The zinc at Century is in the fine grained sphalerite so the ore had to be crushed to 30 micron prior to floatation and resultant concentrate reground to sub 10 micron and progressively cleaned. To recover effectively the zinc needs a longer resonance time to recover effectively.

Given century was a monster the mine and treatment plant was configured to focus on through put rather than recover as that is what optimized returns at the time. They sacrificed recovery achieving low 70% recovery rather than the 85% that it could have done if they slowed the plant down and focused on recovery at a lower through put rate. 8mtpa at 70% v 4-5mtpa at 85%.

New Century are now able to refloat the tailings and give it the extra resonance time it needed originally.

MMG knew this but they ultimately thought it was too small to make a difference to them. Same reason they divested Golden Grove for $200m and that made $120m last year and now has a 15 year mine life now.