Name the metal M, which is extracted based on the following equation

$4\mathrm{M}+8{\mathrm{CN}}^{-}+2{\mathrm{H}}_2\mathrm{O}+{\mathrm{O}}_2\to 4{\left[\mathrm{M}(\mathrm{CN}{)}_2\right]}^{-}+4{\mathrm{OH}}^{-}$$2{\left[\mathrm{M}(\mathrm{CN}{)}_2\right]}^{-}+\mathrm{Zn}\to {\left[\mathrm{Zn}(\mathrm{CN}{)}_4\right]}^{2-}+2\mathrm{M}$

$4\mathrm{M}+8{\mathrm{CN}}^{-}+2{\mathrm{H}}_2\mathrm{O}+{\mathrm{O}}_2\to 4{\left[\mathrm{M}(\mathrm{CN}{)}_2\right]}^{-}+4{\mathrm{OH}}^{-}$ $2{\left[\mathrm{M}(\mathrm{CN}{)}_2\right]}^{-}+\mathrm{Zn}\to {\left[\mathrm{Zn}(\mathrm{CN}{)}_4\right]}^{2-}+2\mathrm{M}$

It is an example of Leaching.

The Leaching is the process of extraction of metals from their ore with the help of a solvent.

In this process, Silver (Ag) and Gold (Au) can be extracted from their respective metal ores with the help of dilute solutions of Sodium cyanide ( $\mathrm{NaCN})$ or Potassium cyanide $\left(\mathrm{KCN}\right)$ in presence of Oxygen $\left({\mathrm{O}}_2\right)$.