Cobblestone Crafting Bug

Hello my name is Bruno, today i was going to find diamonds with my friend, but my pickaxe broken, so i decided to make a stone pickaxe because i don't have iron to craft an iron pickaxe, but when i tried to craft a stone pickaxe, i needed STONE, not COBBLESTONE, i think this is a bug or not, but please, put the cobblestone back to stone weapons, thank you.