Minecraft wiki entry for Printing, associated text: Snapshot 17w06a of update 1.12 brought gravity-affected concrete powder blocks. It also brought concrete, which forms if concrete powder touches water. Concrete powder and blocks come in all of the 16 colors that make up the color spectrum in Minecraft. By telling certain pistons what colors to drop down from a "stock," it's possible for a printer and 3D printer to be built in Survival mode.