July 27 (Reuters) - Barrick Gold Corp ABX.TO
* Barrick's second-half 2017 gold production will be weighted toward fourth quarter - Chief Operating Officer
* Barrick expects higher Q3 cash and all-in sustaining costs, based on sales mix and capex timing -COO
* Barrick appoints Jim Whittaker CEO of Minera Argentina - including Veladero mine; replaces GM Jorge Palmes -C00
* Barrick ramp up at Veladero mine ahead of plan, confident in meeting 2017 output forecast -COO