An ink stick for use in an ink delivery system of a phase change ink imaging device comprises an ink stick body having first and second opposed end surfaces and first and second opposed lateral side surfaces. The ink stick body is rotationally symmetric about a vertical central axis of the ink stick body. The ink stick body includes an interlocking face on the first end surface and a complementarily shaped interlocking face on the second end surface. A key is on each of the first and second side surfaces. The keys of the first and second side surfaces are similarly shaped. The key on the first side surface and the key on the second side surface are rotationally symmetrically positioned with respect to each other about the vertical central axis.