Iron

Iron is one of the 5 resources available for gathering. Iron is collected from Mines, but can also be collected as round rewards on Jotun Ridge.

Upgrading
Iron is used for upgrading the following buildings:
 * Sacred Tree
 * Clan Hall
 * Craft Tower
 * Trade Post
 * Farm
 * Henge
 * Lumber Mill
 * Temple
 * Barracks
 * House
 * Vault