Gulf aluminium output drops 35% amid regional conflict Brent tops $91 amid 11th consecutive night of US strikes LME base metals traded mostly higher on 21 July, supported by tightening exchange inventories and improving market sentiment. Copper led the gains, rising 1.93% d-o-d to $13,885/t, followed by nickel, up 0.92% to $17,085/t, zinc, which gained…