(BLOOMBERG) -- Gold surged the most since the height of the global financial crisis in 2008 after the U.K. voted to exit the European Union, causing turmoil across markets and boosting haven demand.

Bullion jumped as much as 8.1% before paring some of the gain, and futures trading volume was more than four times the average for this time of day. As the pound tumbled against the dollar, gold priced in sterling rallied as much as 19% and mining companies such as Randgold Resources and Barrick Gold advanced.

“The volume we saw last night was unmatched by anything, and we’re nowhere near done,” said Naeem Aslam, chief market analyst at London brokerage TF Global Markets. “The phone’s been off the hook all night. We were around the news wires nonstop.”

Some clients were frustrated that they couldn’t get orders completed quick enough as trades kept being upended by other large positions coming in, Aslam said, as he stepped out of the office for a coffee after working overnight. He said he’s planning to work over the weekend to meet the surge in business.

U.K. voters backed leaving the EU by 52% to 48%, sending shock waves through markets and prompting Prime Minister David Cameron to resign. European stocks and U.S. futures slid, the pound plunged by a record and the euro weakened.

Gold for immediate delivery climbed 5.3% to $1,323.62 an ounce by 8:50 a.m. in New York, the highest in almost a year. Societe Generale SA had said that gold could reach $1,400 in the event of a Brexit.
The metal is up 25% this year as expectations that the Federal Reserve will keep interest rates low weakened the dollar. The U.S. central bank will be even more likely to keep rates on hold following the result of the U.K. referendum, according to Saxo Bank A/S and ICBC Standard Bank Plc.

European gold dealers saw a rush for physical metal, with CoinInvest.com saying it had a record number of U.K. customers interested in buying. Daniel Marburger, a director at the Frankfurt-based firm, said Britannia and Sovereign coins from the U.K.’s Royal Mint were the best sellers in the early hours. ABC Bullion Co., a Sydney-based trader, said new account openings on Friday matched the whole of a normal week.

Haven Demand
“There’s a lot of fragility out there politically and economically,” said Jordan Eliseo, chief economist at ABC Bullion. “It’s a more difficult time for investors and safe-haven assets are the way to go.”

GoldCore Ltd., a brokerage in Dublin, experienced record online sales for the time of day and may have to restrict trading to existing clients if demand remains high, director Mark O’Byrne said by e-mail.

Randgold Resources climbed as much as 29%, the most ever, and was last up 20%. Fresnillo Plc advanced 14% and the two companies were the biggest gainers among the few rising today in the U.K.’s FTSE 100 Index. The BI Global Senior Gold Valuation Peer Group surged 7.4%.

In other precious metals news:
Gold priced in sterling earlier rose the most since at least 2000 and was last up 14% at 966.78 pounds an ounce. Silver rose 3.7% to $17.933 an ounce, after touching the highest since January 2015. Platinum gained 2.3% and palladium declined 2.7%.