Gold prices edged lower on Friday and were set for a weekly decline as investor attention turned to key U.S. inflation data for cues on the Federal Reserve's interest rate trajectory. Spot gold dipped 0.1% to $2,331.15 per ounce as of 0136 GMT. Prices are down nearly $100 from the all-time high of $2,431.29 scaled on April 12, fuelled by geopolitical turmoil.