Cold iron
This iron, mined deep underground and known for its effectiveness against demons and fey creatures, is forged at a lower temperature to preserve its delicate properties. Weapons made of cold iron cost twice as much to make as their normal counterparts. Also, adding any magical enhancements to a cold iron weapon increases its price by 2,000 gp. This increase is applied the first time the item is enhanced, not once per ability added.

Items without metal parts cannot be made from cold iron. An arrow could be made of cold iron, but a quarterstaff could not. A double weapon with one cold iron half costs 50% more than normal.

Cold iron has 30 hit points per inch of thickness and hardness 10.

Cold Iron Firearms constructed out of cold iron allow for a much more precise shot, allowing ammunition to travel more aerodynamically through the barrel. A firearm constructed out of cold iron increases its range increment by 20 ft.
Cost +2,000 gp