Minecraft wiki entry for Diamonds, associated text: After finding the first diamonds and graduating to enchanting, a player should make and carry one Fortune III pickaxe to multiply the diamonds mined in the future. At this point, enchanting the player's new diamond pickaxe with Fortune seems obvious; however, there is a better way: Enchant the diamond pickaxe with Silk Touch, and keep a separate Fortune III pickaxe (which can be left home instead of risked on trips) for valuable ores. If possible, add Mending to the Fortune pickaxe.