Recycle Items Plus Mod 1.7.10 allows you to smelt most items to get 33% of the precious materials used to craft it. The mod adds in 3 new items, Iron Nugget, Diamond Nugget, and Emerald Nugget. Those work exactly like Gold Nuggets. Put the nuggets in all spots in the crafting table, you will get the ingot, and vice versa. The key below explains more.
How to install Recycle Items Plus Mod 1.7.10
Download Links for Recycle Items Plus Mod 1.7.10
For Minecraft 1.7.2
For Minecraft 1.7.10