Iron is a resource that kittens can access after researching Metal Working. Iron is key to many buildings, and is primarily accumulated via Smelters.
- After you research Metal Working, you can build Smelters, which (initially) produce 0.02 iron per tick, at the cost of 0.05 wood and 0.1 minerals.
- After you research Chemistry, you can build Calciners, which (initially) produce 0.15 iron and 0.0005 titanium per tick, at the cost of 1.5 minerals and 0.024 oil.
- The Oxidation and Rotary Kiln upgrades increase the iron output of Calciners by 100% and 75%, respectively.
- Griffins will give you iron in return for 500 wood.*
- Zebras will give you iron (and sometimes other resources) in return for 50 slabs.*
- Despite appearances, Solar Revolution does affect iron production.
- Initial storage capacity is 50.
- After you research Agriculture, you can build Barns, which increase storage by 50 each.
- After you research Construction, you can build Warehouses, which increase storage by 25 each.
- After you research Navigation, you can then build Harbours, which increase capacity by 150 each.
- The Expanded Cargo upgrade gives a 1% bonus to the Harbour capacity for each Trade Ship you build. This effect has diminishing returns, up to a limit of 225%.
- After you research Rocketry and complete the Moon, Piscine, and T-minus Missions you can build Cryostations, which each increase storage by 50K.
- After completing the Helios space mission, you can build Sunforges, which increase iron storage by 1% each.
* All trade amounts returned vary based on the season and the number of Tradeposts you have. See the Trade page for more details.