Block of the Month: Weathered Copper

To get weathered copper you’re going to need some copper and some time. Cram nine copper ingots into a crafting grid, and you’ll get a fresh, shiny, orange copper block. Then put it on the ground and leave it there for a while.

You’ll notice the same slow transition that we did – with little patches of corrosion getting larger and larger until the whole thing is a beautiful shade of green. Specifically, there are four stages in this process – “normal”, “exposed”, “weathered”, and “oxidized”. 

To make it nice and shiny again, you’ll need to do a bit of maintenance. Scrape an axe across it, and you’ll expose some of the original orange color. Keep going and it’ll eventually be good as new again. Lightning can also do the same thing, though rather less predictably.

What if you want to keep your copper in a specific state and not allow it to oxidize? Then you’re going to need to find a way of not letting any oxygen get to it. Burying it in the ground doesn’t work, and neither does submerging it underwater. What does work, though, is smearing it with a nice coating of wax. Grab some honeycomb and use it on a block, and it’ll stay preserved for all time. Want to unwax it again? Grab your axe and scrape the wax coating off, just like before.

So what’s actually going on here at a scientific level? Well, it’s a bit like how iron in the real world gets rusty over time. The pure copper reacts with substances found in the air to produce a green (and poisonous! Don’t lick it!) coating called verdigris. 

That coating is usually just a fraction of a millimeter thick but it’s extremely durable – protecting the copper beneath from further weathering. This durability is why copper is highly popular as a material to build roofs with. You’ll see green copper architecture in many parts of the world – perhaps most famously on New York’s Statue of Liberty.

In the real world, this process can take a long time. In polluted industrial areas, it can take about 15 to 20 years. In rural areas, it can take 30 to 40 years. In arid places with very little moisture in the air, it may not happen at all.

In Minecraft, you won’t need to wait that long but it’s still not fast. A few in-game weeks should do the trick. But don’t rush it! Sit back, and enjoy the slow, beautiful process of chemistry in action.