METALS-Copper ends higher but Greece worries cap advance

* Dollar gains ground against euro on Greece debt downgrade

* Chinese economic data awaited on Tuesday

(Adds detail, comment, updates with closing prices)

By Marie-Louise Gumuchian and Melanie Burton

LONDON, May 9 (Reuters) - Copper ended higher on Monday on a relief rally following steep losses last week, but a downgrade of Greece's credit rating added to global slowdown fears and capped the metal's advance.

Copper for three-month delivery on the London Metal Exchange finished at $8,890 versus $8,825 a tonne at Friday's close. The metal used in power and construction had hit $8,657.50 on Friday, its lowest since early December.

"The market is still in shock from last week. This relief rally is dominated by relatively thin volumes. The dollar has begun to strengthen ... and the pattern is one to sell the rallies at the moment," said analyst Alex Heath of RBC Capital.

"On the whole, the risk remains to the downside ... until we see some clarity out of statistics to indicate that growth is back on line," he said.

The euro pared gains after Standard and Poor's cut Greece's rating to B from BB-, dragging it further into junk territory over concerns that a debt restructuring is increasingly likely.

A stronger dollar makes commodities such as metals cheaper for holders of other currencies.

Commodity markets fell sharply last week, with the Reuters-Jefferies CRB index down 9 percent in its biggest weekly decline since December 2008 despite unexpectedly strong U.S. non-farm payroll numbers on Friday.

Since then, many major commodities have rebounded. Brent crude rose on Monday after losing $16 last week in the biggest ever decline in dollar terms.

CHINESE DATA

Indian non-ferrous metals producer Hindalco Industries said it expected strength in prices and volumes to continue but spiralling input costs were a concern.

The firm, part of the diversified Aditya Birla Group, said it expected aluminium demand in India to grow 8-9 percent in 2011/12.

A slew of Chinese and U.S. economic data could keep volatility high again this week, including inflation numbers that will give some indication of how far the monetary tightening cycle has to run in China, the top driver of commodities demand growth.

"The next batch of Chinese economic data due out over the next two days will ... be vital, particularly in terms of trying to gauge the effectiveness of the Chinese tightening measures," said Standard Bank in a note.

"A combination of high inflation and lower-than-expected growth looks like being the worst option and would likely trigger further weakness.

Copper, tin and lead inventories in LME warehouses rose, the latest data showed.

Nickel stocks fell to their lowest since mid-August, while tin stocks rose to their highest in more than a year, rising 305 tonnes to 21,720 tonnes.

Indonesia's refined tin exports rose 22 percent in April from the same month last year due to improving weather conditions, an official at the trade ministry said.

Indonesia is the world's top tin exporter. A crackdown on illegal mining, tighter export rules, declining onshore reserves and rain that has hindered production in the country have helped drive tin's rally. The metal, which is used in soldering in the electronics industry, hit a record high of $33,600 in April.

Tin finished at $29,795 a tonne from $29,650 at the close on Friday. Aluminium ended $2,612 a tonne versus $2,608. Zinc, used in galvanizing, closed at $2,164 a tonne from $2,140.

Battery material lead ended at $2,300 a tonne from $2,280. Nickel closed at $24,375 versus $24,650 a tonne.

Metal Prices at 1613 GMT Comex copper in cents/lb, LME prices in $/T and SHFE prices in yuan/T Metal Last Change Percent Move End 2009 Ytd Percent

move COMEX Cu 403.30 6.35 +1.60 334.65 20.51 LME Alum 2610.00 2.00 +0.08 2230.00 17.04 LME Cu 8890.00 65.00 +0.74 7375.00 20.54 LME Lead 2300.00 20.00 +0.88 2432.00 -5.43 LME Nickel 24355.00 -295.00 -1.20 18525.00 31.47 LME Tin 29790.00 140.00 +0.47 16950.00 75.75 LME Zinc 2163.00 23.00 +1.07 2560.00 -15.51 SHFE Alu 16690.00 80.00 +0.48 17160.00 -2.74 SHFE Cu* 66980.00 1040.00 +1.58 59900.00 11.82 SHFE Zin 16720.00 390.00 +2.39 21195.00 -21.11 ** Benchmark month for COMEX copper * 3rd contract month for SHFE AL, CU and ZN SHFE ZN began trading on 26/3/07

(Editing by Jane Baird)