Description (From Recipaedia)
A block of pure iron. Very heavy and durable. Extremely resilient to digging and explosions. Can be crafted from multiple iron ingots.
CraftingCombine 9 iron ingots to form 1 solid iron block.
The block may be later broken down to retrieve the 9 ingots.
Iron blocks are primarily used as decoration or building materials. Their extreme strength provides protection where explosion resistance is beneficial.
They're also used to craft Musket.
They are found in the CONSTRUCTION section of the recipaedia.
They only stack up to 4, so are not a very efficient means of storing iron at the equivalent of only 36 ingots per stack.