Copper Golems don’t Oxidize

I have created over 3 stacks of copper golems in a new survival no-cheats world, (I created the world last night. The only setting I have touched was the sleeping percentage, and that was a couple hours in), but all have remained unoxidized for hours. I’ve kept them in a relatively large enclosure, around 30x40, and have been periodically adding more when I have the means. The chests that I left out have oxidized perfectly, but the golems have not aged at all.