* Physical copper premiums in China rising sharply
* Shanghai copper at 6-week high, aluminium at 2-month peak
* Nickel hits fresh 14-month top, up for 16th session in 17
* Coming up: U.S. durable goods orders at 1230 GMT
(Adds details, quotes; previous SINGAPORE)
LONDON, April 24 (Reuters) - Copper touched its strongest level in three weeks on Thursday and nickel surged to a new 14-month peak as seasonal Chinese demand for metals ramped up and concerns over nickel supplies prompted more speculative buying.
All base metals on the London Metal Exchange pushed higher, including tin, which hit a 6-1/2 month high on continued tight supply from major producer Indonesia.
Three-month copper on the London Metal Exchange climbed 0.72 percent to $6,718.25 a tonne by 1015 GMT after hitting a session high of $6,731, its strongest since April 2.
"People are looking for slightly firmer demand out of China. We're saying that Q1 is the cyclical low, and we are expecting the economy to gradually pick up from Q2," said Grant Sporre, head of metals research at Deutsche Bank.
"Today's gains are a combination of the expectation of improvements in the global economy and some data points that have highlighted that many of these markets are potentially not as over-supplied as the most bearish expect them to be."
For example, while many people expect higher mine supply to push the copper market into surplus, the International Copper Study Group said the refined copper market showed a 53,000 tonne deficit in January.
April and May are seasonally strong months for copper consumption in China amid brisk construction activity. Seasonality has now pushed up the gap between spot copper prices and front-month futures in Shanghai to the highest since 2010.
The most-traded July copper contract on the Shanghai Futures Exchange peaked at 47,330 yuan ($7,600) a tonne, its highest since March 10, before settling at 47,250 yuan, up 1.32 percent.
"Demand is picking up right now because April is a strong month for copper demand in China. A lot of Chinese refineries are also selling their copper to the bonded warehouses which limited the supply in the domestic market," said Guo Hao, analyst at Jinrui Futures in Shenzhen.
Copper is being sold in Shanghai at up to 48,280 yuan a tonne on Thursday, over 500 yuan more than the price for front-month copper on the Shanghai Futures Exchange.
But expectations of increased global supply of copper this year have capped gains in prices of the industrial metal which has lost 9 percent of its value this year.
NICKEL TO TOUCH $20,000?
Nickel extended its sizzling rally, gaining for a 16th session out of 17 on Thursday. LME three-month nickel touched a session high of $18,600 a tonne, its strongest since Feb. 6, 2013, before trimming gains to $18,469, up 0.5 percent.
Nickel has gained more than 33 percent this year, far more than other base metals, as an Indonesian ban on exports of unprocessed ore from January tightened supplies of nickel ore which top buyer China uses in the production of stainless steel.
"It's a difficult call to know how much further momentum will take nickel. My call is that it spikes to $20,000 a tonne, but right here I think the market has moved ahead of fundamentals," Sporre said.
LME tin climbed to a session high of $23,849 a tonne, the highest since Oct. 8 last year, before giving up the gains and trading virtually flat at $23,731, down 0.08 percent.
LME aluminium rose 0.4 percent to $1,882.25 a tonne, rising for a second session in three. Shanghai aluminium closed almost 2 percent higher after hitting a session peak of 13,725 yuan, the highest since Feb. 18, regaining more ground after hitting a record low last month.
Three month LME copper
Most active ShFE copper
Three month LME aluminium
Most active ShFE aluminium
Three month LME zinc
Most active ShFE zinc
Three month LME lead
Most active ShFE lead
Three month LME nickel
Three month LME tin ($1 = 6.2376 Chinese yuan)
(Additional reporting by Manolo Serapio Jr; Editing by Pravin Char)