Although zinc compounds have been used for at least 2,500 years
in the production of brass, zinc wasn't recognized as a distinct
element until much later. Metallic zinc was first produced in India
sometime in the 1400s by heating the mineral calamine (ZnCO3) with
wool. Zinc was rediscovered by Andreas Sigismund Marggraf in 1746
by heating calamine with charcoal. Today, most zinc is produced
through the electrolysis of aqueous zinc sulfate (ZnSO4).