37
Is this the most useless block in Minecraft?
(hexbear.net)
I started a new Minecraft world after a long time, the last time being shortly after the update that added the new cave biomes and changed world generation and I'm instantly reminded of how useless copper is. Can't make tools with it, can't light torches with it, can't use it as fuel, and it's all over the depths you'd typically find iron and coal, the two early ores that actually do those things 
you need a lot of that for low density structures and circuits