* Gold holds near $1,430/oz on euro debt, Mideast unrest * Financial markets eye prospect of ECB rate hike this week
* Silver prices extend gains to fresh 31-year high
(Updates prices)
By Jan Harvey
LONDON, April 5 (Reuters) - Gold prices eased on Tuesday after China raised interest rates for a second time this year, though euro zone debt concerns and elevated oil prices linked to violence in the Middle East limited losses in the metal.
Silver also retreated after reaching a 31-year high of $38.77 in earlier trade, but traders remain largely on the sidelines ahead of a key European Central Bank rates decision on Thursday.
Spot gold <XAU=> was bid at $1,430.80 an ounce at 1139 GMT, against $1,436.55 late in New York on Monday. U.S. gold futures for June delivery <GCv1> eased 40 cents to $1,432.60. Silver <XAG=> was lower at $38.14 against $38.42.
While China's move weighed on prices of both metals, they remain firmly underpinned by wider issues spooking investors.
"You have (events in) Libya, debt problems in the EU and concerns about inflation supporting the market. Any changes with these three factors will affect the market," said Ole Hansen, senior manager at Saxo Bank.
"We obviously look at the ECB decision on rate hikes. That's a bit of a given now," he added. "The market is pricing it in at this time, and if the ECB doesn't do anything, we may see the dollar strengthen and we may see a bit of a sell-off."
Euro zone sovereign debt was brought back to the fore by a Moody's downgrade of Portugal, knocking the euro from five-month highs versus the dollar. Worries over the financial health of a number of euro zone economies were a key factor in gold's rally last year. [
]Moody's cut Portugal's sovereign debt rating by one notch, raising concerns that debt problems in the euro zone periphery may prevent the ECB from raising rates three times this year, which the market is pricing in. <ECBWATCH> [
]Oil prices meanwhile remained near their highest level since 2008 as violence simmered in the Middle East and North Africa and as elections in Nigeria were delayed. [
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SILVER HITS 31-YEAR HIGH Silver prices are expected to extend gains after earlier rising towards $39 an ounce, analysts say, lifted both by rising investment as buyers seek a safe store of value and by expectations that industrial consumption will improve.
The grey metal is widely used in electronics manufacturing, and in a range of consumer goods such as washing machines, bandages and socks. [
]Silver has outperformed gold in recent months, rising 22 percent in the first quarter compared with gold's 0.7 percent. The gold:silver ratio, which shows how many silver ounces are needed to buy an ounce of gold, fell to a 28-year low at 37.3 on Tuesday.
"Silver continues to attract investor attention away from gold, and given current sentiment $40/oz looks inevitable in the near term," said UBS in a note.
"While there is the real danger that silver prices have travelled too fast, too soon, for now investors show no sign of being overly tempted to sell, with many looking for silver to chase $50 before that investment decision becomes more relevant."
Among other precious metals, platinum <XPT=> was at $1,778.74 an ounce against $1,779.45, while palladium <XPD=> was at $776.97 against $779.50.
(Additional reporting by Silvia Antonioli; editing by Jane Baird)