Minecraft wiki entry for Block_and_item_duplication, associated text: You will need two book & quill and an anvil. Write any text in one book & quill, and sign it. From then, copy the first book & quill by placing them next to each other in the crafting grid. Take the item you wish to duplicate and rename it to the name of the copied book. From here, you can shift-click the anvil result and duplicate your item.