The Specialized Smelters Mod adds 12 new Furnace-like machines.
The new Smelters can smelt stacks of ores instantly, however they can not be automated like furnaces. You can only smelt ores and cannot smelt stone or cook food.
The normal "Super Smelter" can smelt a whole stack at the click of a button.
You can then specialize the Super Smelter to a specific ore. For example, If you upgrade the Super Smelter to a "Iron Smelter", the for every iron ore you smelt, you get 2 iron ingots. This goes for every other specialized smelter.
There is also a "Super Duper Smelter. which is like the specialized smelters, but work for all the ores".
All the recipes are inside a recipe book, which is provided to you when you first join a world. This mod also works on worlds that have already started, so you can add this mod to your already created worlds.