Metallurgy_3.2.3.zip is a release file of the Minecraft mod Metallurgy, made for Minecraft 1.6.2. It was published on July 16, 2013 and is 0.9 MB in size. For the full description, screenshots and every other version, visit the Metallurgy mod page.
How to install: Put the .jar into the mods folder (.minecraft/mods) and start Minecraft with the matching mod loader profile.