I was in a superflat world, then i found a village. I noticed some of the cobblestone was black and purple (just like a locked chest). When i updated the blocks, the textures (of only the group of blocks that i updated) went normal. I found some torches that were also black and purple. They had a smaller block size, and they had a cube shape. I could not update these to make the textures go normal. When i re-loaded the game everything was normal. Similar to MC-48740. Link to development console: http://pastebin.com/nYDPCZzz .