Fortune is a unique enchantment that gives the enchanted tool’s wielder a chance of getting more of a certain mined item. This enchantment will only work for immediate-drop ores like diamond, coal, and emerald ores.
An enchantment table with a list of enchantments (via screenshots)
For items such as coal ore, diamond ore, emerald ore, lapis lazuli, iron ore, redstone ore, copper ore, gold ore, nether gold ore, nether quartz, and amethyst cluster, Fortune gives a 33% (1/3) chance of multiplying drops by 2. Fortune II gives a chance of multiplying drops by 2 or 3 and Fortune III gives a chance to multiply drops by 2,3, or 4.
For carrots, glowstone, melons, nether wart, tall grass, and wheat, the game uses a uniform distribution which makes the drop rates equal and increases the maximum number of drops by one per level of Fortune. For gravel, the drop rate of flint increased to 14% at the level I, 25% at level II, and 100% at level III.
To enchant your tools with fortune you can use either an enchanting table or an anvil. Enchanting tables will give a random list of enchantments that can be applied to the tool, and their strength can be increased by placing bookshelves around the enchantment table.
The other way is to find an enchanted book with the fortune enchantment on it. With the help of an anvil, players can apply the enchantment to their desired piece of equipment. Both processes require the player to have a high enough experience level.
A diamond pickaxe with fortune III on it (via screenshot)
Fortune is a helpful enchantment when you are mining rare resources such as diamonds, gold ore, and others, as you can receive up to 4 times the default drop amount. It won't work in combination with the Silk Touch Enchantment. It doesn't increase experience drops as well.
A. The maximum level of fortune is Fortune III (3).
A. Yes, you can enchant your diamond hoe with the Fortune enchantment.
A. Yes, trading with a librarian can get you the Fortune enchantment book.