IMO, outside a short term up move in the US$, much of the weakness in gold recently has to do with the rebalancing of various commodity indexes. Since gold bullion has substantially outperformed the majority of other commodities, it has become overweighted relative to other commodities that are included with the commodity indexes. Rebalancing requires that gold be sold to bring it back down to its targeted percentage allocation. Rebalancing has been ongoing for the past few days and the 15th of January is the last day for this rebalancing process.