I was looking into your mod and i found out that it can't oxidize tools and armor normally (because ticks and such), i know this is intended but maybe you could make it so we can DE-OXIDIZE tools and amor with an axe and anvil (or something involving the axe), since you can already in vanilla use the axe to DE-OXIDIZE blocks (i know oxidized tools are better but it would be cool as a mechanic)
image example of epic DE-OXIDIFICATION:

as for oxidizing the items, maybe you could consider throwing the copper tools and armor into a cauldron or right clicking a cauldron (maybe you should dip the tools a number of times to work, wasting water)
incredibly dangerous example of dipping things into water:

anyways thanks for reading, i hope you atleast consider the DE-OXIDIZING system

So, a couple of things I want to consider is compatibility and resource friendliness. Right clicking when tied to a vanilla item would require me to listen to all right clicks, whereas right clicking with a modded item is easier on the processing.

I could add a recipe to "scrape" the items, but I'm less enthused about that. A recipe for every item in my mod can get extensive.

Another developer I was talking to pointed out that water and gunpowder can be used as a way to oxidize items. I may consider using that.

well that sounds like a plan, would be really nice to have a way to oxidize the items, i was thinking of some more ways that could work so here are some:

1. use a wet sponge to oxidize
2. receive explosion damage
3. brew in the brewing stand with gunpowder (dont know how hard it would be)
4. make a custom item that oxidizes copper (a potion or something)
5. leave armor in a armor stand and have it oxidize? (dont know if this would cause lag, maybe leave the tools in a campfire or something)
6. specific timer (not sure if this is still ticks but after like 10 minutes it would oxidize)

besides that i can't think of more ways that wouldn't be overly complicated since is not that usefull to oxidize copper since you could get diamonds instead, i hope you can make it work since it would be really cool, good luck!