Is there a good map in province 15, or should I just continue farming 8-7?
Well province 15 is stated to have bigger chance to drop them. AFAIK it doesnt matter what map in that province you do. But it also costs 5 energy vs 3 in 8-7 or 9-1 so not sure if the total will be any better per energy spent.
I would do the lower one, as they will give more other items in addition to the ores.
I’ve been farming 19-4 for fire chest today, got 8 metal ores from 5 hits… weird…