Frosted copper

 Copper, if placed in a mountain or snowy biome will convert to frosted copper in about 10 Minecraft days. It will also frost if placed next to powder snow. If it is placed in a non cold biome it will thaw out over the course of 4 Minecraft days (powder snow will keep it frosted). Waxing copper will keep it as copper though if you wax it after frosting it becomes a Frosted Waxed Copper Block. It will work for all variants (both weathered and block types), bringing the new longest block name to be ‘Lightly Weathered Frosted Cut Copper Stairs’. It will have a frost look and will freeze water blocks that it touches. It can be crafted into frosted copper ingots which can be made into a frost copper blade. A frost copper blade can be added to a sword in an anvil (this can not have fire aspect) and will freeze the opponent on a hit. Freezing an opponent will give hypothermia (a new effect) and damage the opponent. Adding a frost blade to a sword will minus 3.5 attack damage (to the sword not the player), use 2 durability per freeze hit and add a new tag to the item name.