U.S. copper futures ended firm on Friday, as a sharp plunge in the dollar and falling stock levels helped boost the market ahead of the long holiday weekend, but lingering concerns about the health of the global economy kept prices confined to a tight range for the week.

New York energy and commodity markets will be closed on Monday, May 25, for the Memorial Day holiday. Trading will resume on Tuesday, May 26.

* Copper for July delivery HGN9 climbed 4.65 cents, or nearly 2.3 percent, to close at $2.0975 a lb on the New York Mercantile Exchange's COMEX division.

* Session range from $2.0410 to to $2.1215.

* Market locked in a tight weekly trading range between $2.01 and $2.14. A breakout on either side of the range will produce trending action in that direction - HeritageWestFutures.com futures analyst, Ralph Preston.

* COMEX estimated futures volume at 12,053 lots by 12 p.m. EDT (1600 GMT). Final volume on Thursday reached 19,396 lots.

* Open interest rose by 996 lots to 107,391 contracts open as of May 21.

* Copper recoups nearly all of the prior session's losses on the back of another sharp drop in the dollar and continued declines in LME stocks - MF Global analyst, Edward Meir.

* The dollar sank to a new yearly low on Friday and was on track for its biggest weekly fall in two months amid concerns about the AAA-rating status of the United States.

* Growing worries about the U.S. sovereign rating after Britain's outlook was downgraded the previous day triggered heavy selling in U.S. assets. [USD/]

* A soft dollar typically lifts dollar-denominated copper by making it cheaper to buy for non-U.S. investors.

* London Metal Exchange warehouse stocks <LME/STX1> shed another 2,700 tonnes to 333,375 tonnes on Friday.

* Canceled warrants -- metal tagged for delivery from warehouses -- increased to 52,875 tonnes from 51,850 tonnes the previous day.

* Copper inventories in warehouses monitored by the Shanghai Futures Exchange fell 4 percent to 33,798 tonnes from 35,389 tonnes a week ago.

* China's imports of refined copper rose to a third straight record in April, helping to boost the copper giant's month-on-month apparent demand by 9.8 percent. [ID:nHKG255109]

* COMEX copper stocks CMWSU went up another 790 short tons to 52,501 short tons as of Thursday.

* Copper's gains lag behind stronger rallies in precious metals complex as market psychology dominated by industrial perceptions - Preston.

* Japan's output of rolled copper products fell 48.6 percent from a year earlier to 41,709 tonnes on a seasonally adjusted basis. April output climbed 28.7 percent from March due to a rise in demand from the auto and electronics sector - Japan Copper and Brass Association. [ID:nLM942998]

* LME copper for three-months delivery MCU3 settled up $30 at $4,6100 a tonne.