Gold has broken a critical support level, but there is not much downside left, said Alain Corbani, portfolio manager of Finance SA, who forecasts $2,500 an ounce for gold's upside target.The metal will be caught between conflicting macroeconomic forces next year: slightly higher negative real interest rates, but a weakening U.S. dollar. While gold has a negative correlation with negative real rates, ultimately, the dollar will prevail as the dominant driver of gold during this current phase of the commodity cycle.