When aluminium metal is used as a reducing agent for reducing oxides of metals such as Mn, Fe, Cr etc., the process of reduction is known as thermite process.
Example:
Cr₂O₃ + \(\longrightarrow\) Al₂O₃ + 2Cr

ZnS forms soluble complex Na₂ ​[Zn(CN)₄​] while PbS forms froth.
When the minerals are expected to contain PbS and ZnS, suitable depressants such as NaCN are added.
The added NaCN, selectively prevents ZnS from coming to the froth by forming soluble complex Na₂​[Zn(CN)_4​] and PbS is removed along with the froth.

Reverberatory furnace used for smelting, refining, or melting in which the fuel is not in direct contact with the contents but heats it by a flame blown over it from another chamber.
Blast furnaces are used to produce pig iron from iron ore.

At 673 K, the value of \(\triangle G_{C O, C O_{2}}\) ,is less than that of  \(\triangle G_{(\mathrm{C}, \mathrm{CO})}\)  Therefore, CO can be oxidised more easily to CO₂ than C to CO. Hence, CO is a better reducing ag ent than C at 673 K.

Copper matte chiefly consists of Cu₂S along with some unchanged FeS. When a blast of hot air is passed through molten matte taken in a silica lined converter, FeS present in matte is oxidised to FeO which combines with silica (SiO₂) to form FeSiO₃ slag.
\(2FeS+3{ O }_{ 2 }\longrightarrow 2FeO+2S{ O }_{ 2 }\uparrow \quad ;\quad FeO+\underset { Silica }{ Si{ O }_{ 2 } } \longrightarrow \underset { Slag }{ FeSi{ O }_{ 3 } } \)
When whole of iron has been removed as slag, some of the CU₂S undergoes oxidation to form Cu ₂O which then reacts with more Cu₂S to form copper metal.
\(2{ Cu }_{ 2 }S+3{ O }_{ 2 }\longrightarrow 2{ Cu }_{ 2 }S+2S{ O }_{ 2 }\uparrow \quad ;\quad 2{ Cu }_{ 2 }O+{ Cu }_{ 2 }S\longrightarrow 6Cu+2S{ O }_{ 2 }\uparrow \) 
Thus, copper matte is heated in silica lined converter to remove FeS present in matte as FeSiO₃ slap.