Crusade, how many billions of mobs you killed to get that amount of materials
Around 2500.
had to kill some time until quest mobs/gathering stuffs respawned, so just farmed mobs in the meantime.
Ofc, had to farm Ancient Keberium for that as well, but it´s not that hard to just stay afk in keberium farm alliance for a few hours when you are doing something else anyway.