Block of Emerald

Blocks of Emerald (also known as emerald blocks) are decorative mineral blocks.

Obtaining
Blocks of emerald can only be mined using a iron pickaxe or better.

Usage
Blocks of emerald are often used to store emeralds in a compact fashion, or otherwise used as an expensive construction block.

Beacons
Blocks of emerald can be used to "power" a beacon. The top layer must be at least 3×3 optional lower layers can be adding as 5×5, 7×7, and 9×9 from top to bottom. The layers do not have to be entirely emerald blocks, as they may also contain blocks of iron, blocks of gold, and blocks of diamond.

Trivia

 * Jeb removed the old chest textures in terrain.png to make room for the Block of Emerald next to the other icons of items, causing the locked chest to have the blank, purple "texture" on its sides and the top texture of a Block of Emerald. In a 1.5 snapshot, one side also had the redstone block texture.
 * Emerald blocks are the only storage block to resemble the item they are made from. Coal blocks do have a similar texture to their item though