Emerald

Emeralds are minerals used for currency normally obtained by and used for villger trading. They can be found in desert and jungle temples as well as mined from the Emerald Ore. The ore can be found at layers 1-32 in Extreme Hill biome types, making emeralds the rarest ore in the game.

Like Diamonds, Coal, Redstone and Quartz, Emeralds can be stored in 9 pieces by crafting Emerald blocks. If you need the Emeralds back placed the blocks back in the crafting table.

Emeralds primary use is village trading as well as powering the beacon. To trade with villagers the player must place the required item(s) in the left slot, they will then be given the item displayed on the right. Villagers will tend to sell emeralds instead of buy them, either way you will still have to give an item for a succesful trade.

In the Xbox edition village trading is slightly different becuase of the different inventory designs. Instead you will have to have the required in the inventory and just simply click on the item you wish to take. In both editions most of the trades made by the villagers are the same.