With Nullius (https://mods.factorio.com/mod/nullius) and this mod both active, iron is reddish-brown on the map but, still vanilla blue in the inventory. Not sure of other ores (they’re late-game in Nullius).

Also, Nullius adds a few new ores. Those look realistic enough already though.

I'll try to look into that when I have some time. I don't promise, it will be this week.

I totally did not completely forgot about it.
Nullius, you say? Let's see...

For some reason Nullius made an explicit effort to override the icon back to default, so I had to override that override.
Anyway, I've changed the item icon and also the technology "Checkpoint: iron ore assay".

Let me know if any other texture in that mod needs to be changed by this mod.

But to be honest I don't think it's easy to fit your mod into Nullius because of its very special setting.

Reason: Nullius features a planet WITHOUT free oxygen (even in water!) so ore and copper shouldnt become "realistic color" cuz they won't be oxidized. Your character is an android so it don't need any oxygen to operate.

But later you release free oxygen into atmosphere for terraforming. Iron and Copper should become oxidized slowly and partly depends on oxygen level, and all ores and veins become fully oxidized once oxygen level objective reached (which should happen right before you finish all your objectives and win the game).

I guess this is quite hard for you to do so.

(Uranium is OK for change, the problem is iron and copper.)

That’s an interesting point. However to my knowledge, at longer timescales water and CO2 react with iron as well. I’m not a geologist to explain the details and consequences though.

Uranium is OK for change

It’s no different from iron. Pure uranium is gray. It’s the ore what is yellow.

I'm not a geologist so I cannot say how those metals would look on a planet without oxygen in the atmosphere. Mars has almost no oxygen and it's still red so maybe if you would give the ores enough time...?

Making the colors change over time would be indeed hard to program. The game expect you to specify the textures for ores only once, at startup. That's why you have to restart the game after changing the mod settings. I don't know it there is any API that would let you change ore color depending on some variable.
I'll pass.

If you want to have a changed color for uranium only, you can turn off other ores in the mod settings.