▁the ▁ 1 7 th ▁century . ▁German ▁chem ist ▁Andreas ▁Mar gg raf ▁is ▁usually ▁given ▁credit ▁for ▁discover ing ▁pure ▁met all ic ▁z inc ▁in ▁a ▁ 1 7 4 6 ▁experiment ▁by ▁he ating ▁a ▁mixture ▁of ▁cal am ine ▁and ▁char co al ▁in ▁a ▁closed ▁vessel ▁without ▁co pper ▁to ▁obtain ▁a ▁metal . ▁Exper iments ▁on ▁fro gs ▁by ▁the ▁Italian ▁doctor ▁Luigi ▁Gal v ani ▁in ▁ 1 7 8 0 ▁with ▁br ass ▁p aved ▁the ▁way ▁for ▁the ▁discovery ▁of ▁elect rical ▁batter ies , ▁gal van ization ▁and ▁c ath od ic ▁protection . ▁In ▁ 1 8 8 0 , ▁Gal v ani ' s ▁friend , ▁Aless andro ▁Vol ta , ▁invent ed ▁the ▁Vol ta ic ▁p ile . ▁The ▁bi ological ▁importance ▁of ▁z inc ▁was ▁not ▁discovered ▁until ▁ 1 9 4 0 ▁when ▁carbon ic ▁an h yd r ase , ▁an ▁en zym e ▁that ▁scr ubs ▁carbon ▁dio x ide ▁from ▁blood , ▁was ▁shown ▁to ▁have ▁z inc ▁in ▁its ▁active ▁site . ▁ ▁Cad m ium ▁In ▁ 1 8 1 7 , ▁cad m ium ▁was ▁discovered ▁in ▁Germany ▁as ▁an ▁imp urity ▁in ▁z inc ▁carbon ate ▁min er als ▁( cal am ine ) ▁by ▁Friedrich ▁St rom ey er ▁and ▁Karl ▁Samuel ▁Leb ere cht ▁Hermann . ▁It ▁was ▁named ▁after ▁the ▁Latin ▁cad m ia ▁for ▁" cal am ine ", ▁a ▁cad m ium - b