* US silver futures hit 31-year high at $49.82/oz
* Spot gold rises to record of $1,517.71/oz
* Coming up: U.S. NAHB housing market index; 1400 GMT (Adds details, comments; updates prices)
By Rujun Shen
SINGAPORE, April 25 (Reuters) - Spot silver surged more than 5 percent to above $49 ounce on Monday, buoyed by a weak dollar and strong physical demand in Asia that also propelled gold to a record high for a seventh consecutive session.
Spot silver hit a 31-year high of $49.31 an ounce, before easing to $49.16 by 0854 GMT. The level was 17 cents off a 1980 record high, according to Reuters data. It was heading for its biggest daily gain in five months.
"Everyone is buying," said a Hong Kong-based dealer. "There is stop-loss buying, as well as a good buying interest from China."
The dollar index languished around a three-year low on Monday, with investors expecting further weakness on concerns about the size of the U.S. budget deficit and the expectation that interest rates in the world's largest economy would remain low.
Concerns about rising inflation in many parts of the world have also made precious metals attractive to investors.
Ongoing unrest in the Middle East and North Africa, and sovereign debt crisis in the euro zone, helped enhance the lure of precious metals.
Spot gold hit a record high of $1,518.10 an ounce, before easing to $1,517.80, up nearly 1 percent.
Precious metals futures contracts rallied along with spot prices.
U.S. silver futures SIcv1 jumped 8.2 percent to $49.82 an ounce in unusually large trading volume, just about 50 cents off its all-time peak of $50.35 hit on Jan. 18, 1980. The contract eased to $49.17 an ounce on Monday.
The U.S. contract was catching up with moves on physical silver on Friday, when a holiday closed the futures market.
U.S. gold futures GCcv1 also rose to a record high, at $1,518.6.
Spot silver broke through resistance at $48 per ounce. That triggered some automatic buying, analysts said.
"As the market edged higher, a series of stop-loss buying was triggered, especially after silver rose above $48," said Yuichi Ikemizu, Tokyo branch manager of Standard Bank.
Technical analysis showed silver could be headed towards $54.78 per ounce, said Wang Tao, a Reuters market analyst.
Buying interest in physical silver has jumped in markets from China, India to the Middle East.
"Everyone wants a piece of silver, right from a cab driver to a professional," said Harshad Ajmera, proprietor of Kolkata-based JJ Gold House in India, "It looks like the whole of one billion population is chasing silver."
For retail consumers, silver at near $50 an ounce is still a lot cheaper than $1,500 gold, but for investors, silver is more expensive relative to gold than it has been for more than three decades.
Silver prices have climbed nearly 60 percent so far this year, after jumping more than 80 percent in 2010. Silver's rally this year has outpaced gold's 7 percent rise and the 10-percent gain in the 19-commodity Reuters-Jefferies CRB index .
Despite silver's rise relative to gold, it was still attracting investors.
Holdings in the world's largest silver-backed exchange-traded fund, iShares Silver Trust , have risen by 2.4 percent so far this year, compared to a 4 percent decline in the holdings of SPDR Gold Trust, the world's top gold ETF.
"The world is in love with the stuff right now. Silver ETFs are doing a roaring trade and silver bullion is being snapped up by retail investors," said a trader at an international bank in Singapore.
"But I would caution against chasing prices right now. There is way too much fizz in the market right now."
Precious metals prices 0854 GMT Metal Last Change Pct chg YTD pct chg Volume Spot Gold 1517.80 14.25 +0.95 6.93 Spot Silver 49.16 2.49 +5.34 59.30 Spot Platinum 1829.99 19.19 +1.06 3.54 Spot Palladium 772.72 7.24 +0.95 -3.35 COMEX GOLD JUN1 1518.20 14.40 +0.96 6.81 22742 COMEX SILVER MAY1 49.17 3.11 +6.75 58.92 42005 Euro/Dollar 1.4597 Dollar/Yen 81.98 COMEX gold and silver contracts show the most active months (Additional reporting by Lewa Pardomuan, Nick Trevethan in SINGAPORE, Siddesh Mayenkar in MUMBAI, Chikako Mogi in TOKYO; Editing by Ed Lane)