iden ▁is ▁expanded ▁and ▁modern ised . ▁The ▁Out ok ump u ▁Group ▁is ▁incorpor ated , ▁and ▁the ▁z inc ▁sm elter ▁becomes ▁known ▁as ▁Out ok ump u ▁Z inc ▁O y ▁and ▁the ▁co pper ▁and ▁nick el ▁sm el ters ▁as ▁Out ok ump u ▁Har j aval ta ▁Met als ▁O y . ▁▁ 1 9 8 8 ▁The ▁Spanish ▁min ing ▁company , ▁Ap ir sa ▁SL , ▁becomes ▁a ▁subs idi ary ▁of ▁Bol iden . ▁▁ 1 9 8 7 ▁The ▁Swedish ▁industrial ▁con gl omer ate , ▁T rel le borg ▁AB , ▁takes ▁a ▁cont rolling ▁interest ▁in ▁Bol iden . ▁▁ 1 9 7 9 ▁Bol iden ▁bu ys ▁Paul ▁Ber gs ö e ▁& ▁Son . ▁▁ 1 9 7 7 ▁Production ▁starts ▁at ▁the ▁Irish ▁z inc ▁mine , ▁T ara . ▁▁ 1 9 7 0 ▁Production ▁of ▁al umin ium ▁flu or ide ▁begins ▁at ▁O dd a . ▁In ▁Ireland , ▁T ara ▁disco vers ▁the ▁big ▁z inc ▁and ▁lead ▁depos it . ▁▁ 1 9 6 9 ▁Oper ations ▁begin ▁at ▁the ▁z inc ▁sm elter ▁in ▁K ok k ola . ▁▁ 1 9 6 8 ▁M ining ▁operations ▁start ▁at ▁A it ik . ▁▁ 1 9 6 7 ▁The ▁Bol iden ▁mine ▁is ▁closed ▁down . ▁Out ok ump u ▁dec ides ▁to ▁establish ▁its ▁own ▁z inc ▁sm elter ▁in ▁K ok k ola . ▁▁ 1 9 6 4 ▁Bol