I've installed the mod to see how it all looks. The enriched ores are created by applying acid and water to the vanilla ores.
I've research how copper react to sulfuric acid and it seems that it doesn't dissolve if the acid is diluted so it fits pretty nicely. The process of enrichment is the Krastorio is probably to wash off everything that is not copper, using diluted sulfuric acid. This is a stretch because apparently this acid doesn't have a strong effect on rocks either but I would say it is close enough. If we go with this way of reasoning, the color of the enriched ore is actually correct because while the diluted acid doesn't effect pure copper, it removes copper oxide which is the very thing that gives the ore that greenish blue color.
With iron the problem is more complicated because, AFAIK, the acid should dissolve it completely so maybe my idea how the purification process works is wrong after all. Also, I'm not a chemist.
Regardless of how close to the truth my guesses are, I don't think that metal oxides should survive contact with sulfuric acid.
I'll pass on changing colors of these enriched ores until I have some arguments on why they should remain oxidized after the enrichment process.
