The metal extended gains from last Friday, when data showing a rising US unemployment rate fed investor hopes for more aggressive stimulus by the Federal Reserve. Short-covering also helped prices to rebound from last week's weekly drop.
Trading volume in US gold futures, however, was poised to finish at less than half its 30-day average, as some investors questioned whether central banks would come through with more gold-supportive monetary action.
"The market is not committed to this move in gold, which is carried forward from last Friday. Gold has been stuck in the middle of the range, waiting for a new impetus to push it through to higher levels," said Frank McGhee, head precious metals trader at Integrated Brokerage Services LLC.
Spot gold was up 0.6 percent at $1,612.56 an ounce by 3 p.m. EDT (1900 GMT).
US gold futures for December delivery settled up $6.90 an ounce at $1,616.20.
Volume was at around 77,000 lots by 3 p.m., versus its 30-day average of about 169,000 lots, preliminary Reuters data showed.
A combination of gains in crude oil futures, the euro and US equities also lifted gold prices.
Year-to-date, gold is up 3 percent.
Gold prices have been stuck in a $150 trading range between $1,675 and $1,525 an ounce in the past three months, as a lack of firm commitment by central banks to stimulate failed to attract new buying.
Speculation that the Fed may have to unleash another round of quantitative easing, or printing money to buy bonds to keep interest rates low, has firmly underpinned gold prices for the last several years.
Despite improved US hiring last month, most Wall Street economists still expect the Fed to launch another round of monetary stimulus this year, with the majority forecasting action as soon as September.
SHIPMENTS TO CHINA DOWN, ETF GAINS
Physical and investment gold demand was mixed.
Gold shipments from Hong Kong to mainland China, which is challenging India to become the world's biggest gold market, fell 10 percent in June from the previous month.
Inflows into gold-backed exchange-traded funds also picked up after a soft July, with data from the largest showing its holdings up 3 tonnes so far this month.
Among other precious metals, silver was up 0.7 percent at $27.95 an ounce, while spot platinum edged up 0.1 percent at $1,398.24 an ounce and spot palladium rose 1.4 percent to $575 an ounce.
Gold maintained its premium over platinum at above $200 an ounce on Monday, a level it surpassed last week for the first time since early January.