This is an extensive Alloy mod of my own focused on real ores and real Alloys and combines a wide variety of inputs from other mods. Its focused on creating 'real world' alloys from the existing elemental metals rather then adding 'fantasy' elements and alloys. I also aimed for a fully binary system, every alloy is formed from 1 bar each of two different metals. The complex alloys of three or more metals are formed with either a 2 bar or 4 bar reaction and all such reactions are 'logical' in that nothing is being created or destroyed or changing type. I've also made all the Alloying reactions fuel-less and ores comparatively twice as rich. Most metal values have been modified for balance/realism.

A Diagram of the numerous new alloys and their reactions can be seen here
http://i40.tinypic.com/2a8pzpf.jpg

All smelting now produces one of three types of Slag. Slag can be refined further in a reaction that takes two bars and yields on average 3/4 of a bar of metal, some balance testing will reveal if this is appropriate, the slag are called Iron slag, Copper slag and Lead slag, each produces a different combination of metals researched to be appropriate to the actual content of slag from metal smelting.

I also redesigned the whole Ore system, each ore is in some way unique and their are a half dozen new ores that are based on research into prospecting field guides, I've tried to give them as colloquial a name as possible and a good variety of colors. Smelting is more random now with each ore having a number of 'rolls' on producing a metal bar, all the rolls are 50/50 probability and the richest metals get 5 rolls, the most precious ores only 1 or 2. Most of the new ores are bi-metallic, Lead should be much more common as well.

Iron is more complex, their are now 5 forms of Iron, Bloom Iron, Pig Iron, Wrought Iron, Cast Iron and good old Steel. This overly complex process is designed to make Steel harder to get and one up the current Iron system with one even more needlessly complex and realistic.