Just as the total population of illegal immigrants in the U.S. has declined since 2007, the proportion of illegal immigrants in the workforce has also declined; in 2012, illegal immigrants made up 5.1% of the U.S.'s civilian labor force.
Iron Ore is a common ore found almost everywhere in a Minecraft World. Iron ore generates around and below sea-level in the Overworld. It is a crucial material to gather during the early stages of the game, since it can be made into an iron pickaxe capable of mining all types of ores (including diamond). Every Iron Ore block contains enough iron to make one Iron Ingot, when it is smelted.
Pickaxes are one of the most commonly used tools in the game, being required to mine all ores and many other types of blocks. Different qualities of pickaxe are required to successfully harvest certain ores and blocks. For example, while stone can be mined with any pickaxe, gold ore must be mined with an iron pickaxe or better, or else the player will harvest no ore. Different pickaxes also mine many materials at different speeds (see the Speed and durability table below).