What is the best level for mining in Minecraft?

What is the best level for mining in Minecraft?

Due to being the safest layers to mine where all ores exist in reasonable quantities (especially diamond), layer 10 to 15 are usually considered the best area in which to start mining.

What is the best level to strip mine for diamonds?

I would recommend to strip mine at y11, this is because it is above lava and you can find any ores at this level. If you bring a water bucket you can pour it over any lava you mine into. Therefore in my opinion y11 is the best level to strip mine. I hope this helps, good luck finding diamonds!