Iron Ore

Iron ore is a raw resource extracted from iron nodes, that can be melted into steel or directly used in many crafting recipes.

It is the most basic metal for crafting tools, weapons and armors.

Acquiring
Iron ore can usually be found between the soft earth and the rocky earth light (the 1st and 2nd layers in the diagram at the right) and can often be found near veins of coal.

Drops
Iron ore can drop from theses creatures when slaughtered: And a lot of other creatures drop items that can be easily disassembled to get iron ores.
 * Keeper of the Altar (30 ores)
 * Mechanical Guardian (10 or 15 ores)

Crafting recipe
Iron ore can be crafted when the Substance Transformation tech is unlocked, which only happens in the Underground World.