Iron Ingot

Iron Ingots are the metal obtained from the smelting of iron ore. They are used to make a wide variety of items such as iron tools as well as minecarts, minecart tracks, compasses, armor and buckets and more. Iron tools are capable of mining all blocks that diamond tools can, with the exception of obsidian. This makes it one of the most useful items in-game. Iron tools are considered in the middle-tier level, one tier below diamond tools.

Iron ingots can be obtained from smelting iron ore, placing blocks of iron into a crafting grid, dungeons, strongholds, abandoned mineshafts, NPC village and Nether Fortresses chests, and by killing iron golems and zombies.

From chests
Iron ingots have a chance of appearing in dungeons, strongholds, abandoned mineshafts, NPC villages, and Nether Fortress chests.

From iron golems
Iron Golems drop 3-5 iron ingots upon death. For this reason Iron Ingots are renewable as Iron Golems can spawn when enough Villagers are present.

From zombies
Zombies have a rare chance of dropping an iron ingot.

Trivia

 * While Minecraft does distinguish between ores and metals, it does not have a "steel" item separate from iron; flint and steel is crafted directly from an iron ingot.
 * Iron Ingots are the most versatile item in the game, being used in 26 crafting recipes (27 in 14w07a+). The second most versatile item is Wood Planks with 23 recipes. Technically, if the Nether Reactor Core is counted, Iron Ingots are used in 27 recipes (28 in 14w07a+), but the Nether Reactor Core is exclusive to the Pocket Edition, and some crafting recipes that use them are not in the Pocket Edition (such as Iron Doors).

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