This mod adds new ores and alloys through the vanilla dimensions. Overworld contains common ores and alloys, while Nether adds fantasy ores and alloys then End adds "galactic ores". Also, this mods doesn't add new machines or/and tools that Vanilla doesn't provide, but uses nuggets instead to craft alloys. So, you don't lose the vanilla feel.

Current features :

5 Overworld ores and 7 Overworld alloys
3 Nether ores and 3 Nether alloys
2 End ores and 1 End alloy
Tools set for each metal, with Vanilla relative values*
Nuggets and blocks for each metal
Alloy ingot crafting by combining nuggets (Vanilla style)
Ores for each metal (even alloys) for each vanilla dimension, if you want to customize your map.

*This means that if you have a mod that enhances vanilla tools, like golden tools, each tools that are relative to gold are improved too.

! More info are available on the Minecraftforum topic !

http://www.minecraftforum.net/forums/mapping-and-modding/minecraft-mods/2664475-wealth-of-underground-add-new-ores-and-alloys

Planned features :

Config file, for ore generation and alloy crafting.
More metals, specially for mid-tier and end-tier set.
Horse armor
Balancing

English isn't my native language. It is possible I can make mistakes.

Wealth of Underground