Furnace

The Furnace is unlocked at Base Level 13 and can be placed in one of the garden plots to use. You can also acquire it earlier from another player and research it.
It costs 50 clay and 50 stone to build each one.
You will need coal to smelt ore. For example: 100 iron ore yield 20 metal in 1hr 45mins and consumes 10 coal to run for that amount of time.
Smelting quantities
* 10 Wood -> 5 Charcoal - 5 min
* 10 Iron -> 2 Metal - 10 min
* 10 Clay -> 2 Clay Brick - 20 min
* 10 Amethyst -> Amethyst Bar - 15 min
* 10 Metal -> Steel Bar - 25 min
* 10 Emerald -> Emerald Bar - 30 min
* 10 Gold -> Gold Bar - 40 min
* 10 Obsidian -> Obsidian Bar - 45 min
* 10 Diamond -> Diamond Gem - 1 hour