Oil of Cosmetic Enhancement

After spending 10 minutes massaging this oil into an item smaller than a 5-foot cube, it permanently changes the item’s cosmetic appearance. This might change the item’s colors, add intricate designs, or make it blend into its environment. The oil causes no damage and leaves no residue, and it only works on nonmagical items made out of natural materials (such as cotton, parchment, stone, or wood).