Copper Blocks (and all its variants) were introduced to Minecraft in version 1.17, and they brought an interesting new game mechanic with them: Oxidation. The process of oxidation in Minecraft converts Copper Blocks from their shiny, bronze normal color to a greenish hue. In this guide, we explain how long it takes for that to happen in various conditions.
The average time a Copper Block takes to advance from the Unweathered State to the Fully Oxidized state is anywhere between 50 minutes and 70 minutes.
The oxidation process mostly depends on Random Ticks. Without going into too much detail, a Random Tick in Minecraft is an inconsistent occurrence of a Block Update that applies by random chance (ie. growing plants or expanding fire) instead of some other cause (such as receiving light or a Redstone signal). Since oxidation depends on these Random Ticks, it can advance to the next stage in seconds, or it could take hours.
Altering the Speed
The only way to slow the speed of Oxidation is by having another Copper Block with a lower oxidation level within four blocks (Manhattan distance) of the Copper Block.
As of now, there is no way to naturally speed up or slow down the oxidation process in Survival. However, it can be altered in Creative Mode via the following command:
/gamerule randomTickSpeed nAmount (replace nAmount with the desired amount)
The above command doesn't actually make the oxidation faster, but increases the amount of blocks affected by Random Ticks in a given chunk, including Copper Blocks.
Since this is a new mechanic, that's all there is to know! This information may change over time based on future updates to the game.
We have more great coverage and guides for Minecraft 1.17. Check out our Minecraft Homepage for the latest information available for the Caves and Cliffs Update!