Gold bars are pictured at the Ginza Tanaka store in Tokyo October 23, 2009.
The central bank story has offset some selling by investors as seen in the world's largest gold-backed exchange-traded fund, SPDR Gold Trust.
SPDR's holdings fell 0.055 tonnes to 1,108.344 tonnes on Thursday, marking the first decline since October 30.
Silver was bid at $17.48 from $17.37 late on Thursday, platinum at $1,349 from $1,353.50 and palladium at $329.50 from $328.50.
(Editing by Sue Thomas)