I did some testing and I am curious to confirm the base rate for each of the ores of the quarries. It seems that it might be better to only have high yield HQM Quarries fully upgraded.
For example, a Quarry over a Metal Ore Site (14.3/min) will always give that yield, multiplied by the level, when upgrade to Level 4 (which would otherwise unlock Metal Ore).
However, my HQM Quarry when upgrade to 4 unlocks Metal Ore at a base rate of 22.5/min which seems really good.
Was this intentional then? I haven't been able to test what the base rate of HQM is for a Quarry site not over HQM but if that is high maybe it is better to just find a Quarry site that only yields stone and max it out.