Gold prices plunged as much as 4% to their lowest in more than five years on Monday as sellers in top consumer China offloaded the metal.
Investors have been finding less and less reason to hold gold as an insurance against risk, with the dollar strengthening ahead of what is expected to be the first increase in U.S. interest rates for nearly a decade.
Spot gold fell $45.55 to its weakest since March 2010 at $1,088.05 an ounce shortly after the Shanghai Gold Exchange opened, with volumes soaring to a record.
It regained some ground, trading above the key $1,100 support level, but was still down 2.2% at $1,108.18 an ounce by 1355 GMT.
Spot platinum fell for the fifth straight session, down 5% to a fresh 6-1/2-year low of $942.49 an ounce, due to oversupply, sluggish demand and weaker gold prices, which encouraged speculative selling.
"Illiquidity was important in the Asian overnight move, with Japan and other countries on holiday...it was just a bit of a bear raid and there was nobody on the other side to mop up the selling," Societe Generale analyst Robin Bhar said.
"We have breached significant support levels, we know U.S. rate hikes are coming, there is no inflation and there is no catalyst to hold gold when other markets are doing better."
Gold fell more than 1% on Friday, pressured by increased bets on a Federal Reserve rate rise this year, which would increase the opportunity cost of holding the metal.
More than 3 million lots traded on a key contract on the Shanghai Gold Exchange, compared with fewer than 27,000 lots on Friday, Reuters data showed. Before Monday, the volume for July had averaged fewer than 30,000 lots.
Traders said it appeared that sellers had taken advantage of a low-liquidity environment, with Japanese markets shut for a public holiday, fuelling speculative selling.
"The break of the critical $1,130 support level now makes the technical picture look very weak," ANZ said. "Short-term supports sit at $1,085 and $1,050, while topside resistance at $1,130 looks pretty solid."
In wider markets, the dollar hit a three-month high against a basket of currencies, making dollar-priced gold more expensive for holders of other currencies.
China said on Friday its gold reserves were up 57% at 1,658 tonnes at the end of June from the last time it adjusted its reserve figures more than six years ago.
"This implies stockpiling of around 100 tonnes per year, which is dramatically lower than market expectations," Citigroup said in a note.
Palladium dropped as much as 3.4% to its lowest since October 2012 at $593 an ounce, before cutting some losses to trade down 1.4% at $605.25.
Spot silver, the least hit among precious metals in Monday's slide, was off 0.5% at $14.78 an ounce.