Gold struggled to regain lost ground on Wednesday after tumbling nearly 2 percent in the previous session, as the minutes of the US Federal Reserve's last policy meeting showed diminishing appetite for further monetary stimulus. Spot gold edged down 0.1 percent to $1,643.30 an ounce by 0633 GMT, after posting its biggest one-day decline in three weeks. Prices dropped below $1,640 on Tuesday. US gold dropped 1.6 percent to $1,645.00, tracking weaker spot prices.