The FCA is reviewing the benchmark setting for gold as part of a wider investigation into global rates, Bloomberg has reported.
Bloomberg says a source close to the regulator has confirmed it is taking a preliminary look at the way benchmarks for gold are set.
The London gold fixing is set twice per day at 10:30am and 3pm by a group of five banks.
If the FCA decides to take the matter further, it will add to growing scrutiny of financial benchmark setting after the London interbank offered rate was overhauled after rate-rigging investigations.
Trade in foreign exchange markets is also under review by the FCA and a number of global regulatory agencies.