how i can create iron farms

[brayiwins]

i see some houses when i was raiding with iron 'farms' , he has iron blocks to mine in his house and are so much, i dont know how to doit but i want to know how

 

[YoussofHD]

They're called Ore pile placers. They're just ore piles that can be placed anywhere you want.

You can purchase them here: http://minebuilders.buycraft.net/category/731870