Two blocks with the same name

I'm not sure if this is a bug, but when I'm making a mod, I noticed there are two blocks named "Smooth Red Sandstone" in the Block/item selector, one of the Smooth Red Sandstone have an icon of the Cut Red Sandstone, and the other looks normal, and same goes for the Smooth Sandstone, I'm not sure if this is normal. Sorry if this problem already existed, I have tried to find if this topic already existed.