In the isolation of metals, calcination process usually results in :

Solution :
Calcination is the process of converting an ore into its oxide by heating it strongly below its melting point either in absence or limited supply of air. It is usually done to convert metal carbonates and hydroxides to their respective oxides.
\[\begin{align} & \underset{\text{Limestone}}{\mathop{CaC{{O}_{3}}}}\,\xrightarrow{\Delta }\underset{\begin{smallmatrix} \text{Calcium} \\ \,\,\,\text{oxide} \end{smallmatrix}}{\mathop{CaO}}\,+C{{O}_{2}}\uparrow \\ & CuC{{O}_{3}}.Cu{{\left( OH \right)}_{2}}\xrightarrow{\Delta }2CuO+{{H}_{2}}O\uparrow +C{{O}_{2}} \\ \end{align}\]