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Cold Iron
Trade Good [Cold Iron, Crafting Material, Trade Good] Rare
Cold iron is a rare metal which sometimes used in the creation of armor and weapons. It is very expensive and difficult to work with when compared to traditional metals. Due to its magical nature, the metal cannot be heated very much or it will lose its special properties. Because of this, it takes 3 times as long for a weapon or piece of armor to be made out of this material as opposed to standard materials. Since the metal cannot be smelted, all items made from it must be worked from a single piece of metal.
Cold Iron Weapons:
An metal weapon, made with cold iron, will cause an extra 1d4 damage to fey, undead, and fiends it it hits them. It also counts as a magic weapon against these creatures for purposes of immunity and resistance. Due to the expense, cold iron is often applied as a wire (made by pulling or swaging) and then inlayed into the weapon, rather than making the whole weapon of the metal.
Cold Iron Armor:
A piece of armor incorporating (usually gilding or edging) cold iron gives the wearer (or wielder in case of a shield) advantage on spells and spell-like abilities cast by Fey, Undead, and Fiends. In addition, if attacked by these types of creatures that make contact with the wearer (i.e. bite, slam, touch, etc.), the attacker takes 1d4 damage (as if from a magic weapon). Only metal armor (and studded/reinforced leather) and metal shields may be gilded or edged in cold iron. As with weapons, due to the expense, armor is usually inlayed with cold metal wire, rather than making the whole armor of the metal.
Cold Iron Barriers:
Fey, undead, and fiends have difficulty passing a barrier of cold iron. To do so, they must first pass a constitution check of DC 15. This is why some graveyards have cold iron chains surrounding them, to prevent the dead from rising as undead and leaving the graveyard.
Cold Iron Magic Weapons:
Magic weapons that are made of cold iron function as normal magic weapons, losing the cold iron ability unless they are in an anti-magic field.
Expense:
Cold iron ore is worth its weight in gold, 50gp per pound.
Worked cold iron items (weapons, armor, barriers) cost 100gp per pound of worked metal, and take 3 times as long to make.
Cost: 50gp Weight: 1lb