Metallurgy is defined as a branch of chemistry that deals with,
1.Extraction of metals from ores.
2.Refining of crude metal.
3.Producing alloys and the study of their constitution,structure and properties.
4.The relationship of physical and mechanical treatment of metals.
The extraction of metals cannot be carried out by any universal method because extraction of each metal requires different methods of extraction.
Eg: Nobel gases such as Au,Ag are extracted by electrolysis.Heavy metals like Cu,Zn,Fe,Sb are extracted by roasting and smelting methods.