* Support for copper at $6,250 and $6,220
* LME copper stocks have more than doubled since last week (Updates with official prices, adds comment)
LONDON, Oct 2 (Reuters) - Copper prices hit seven-week lows on Friday as demand and economic growth concerns were reinforced by news that U.S. President Donald Trump had tested positive for the coronavirus, as well as a firmer dollar.
Benchmark Copper on the London Metal Exchange (LME) firmed 0.5% to $6,418.50 a tonne in official rings. The metal used widely in power and constructions earlier touched $6,269, its lowest since Aug. 14.
“The news about Trump is bearish for industrial metals because he is seen as wanting to support growth and markets,” one metals trader said.
“Copper stocks are up and the dollar is firm.”
U.S. PRESIDENT: Trump said he and his wife, Melania, have tested positive for the coronavirus and will go into quarantine, only a month away from November’s presidential election.
“Although Trump seems to be healthy for the time being now, it raises concern about who else is sick, especially among the top echelons of Washington’s leadership,” said ED&F Man Capital Markets analyst Edward Meir.
“But we have to suspect that the usual business of government will plough ahead, with virtual meetings now likely replacing any in-person get togethers.”
DOLLAR: The Trump news triggered purchases of the U.S. currency, a strengthening of which makes dollar-priced commodities more expensive for holders of other currencies and can weigh on demand.
Funds use this relationship to generate buy and sell signals using numerical models.
TECHNICALS: Support for copper prices comes at $6,250, an area of congestion from the middle of August. A break below that could prompt an accelerated move towards the 100-day moving average of $6,220.
STIMULUS: Also weighing on markets were signs that the United States might fail to agree a bipartisan deal on a proposed $2.2 trillion stimulus package.
OTHER METALS: Aluminium was little changed at $1,740, zinc fell 0.4% to $2,317.5, lead lost 1.3% to $1,783.5, tin gained 1.3% to $17,530 and nickel was down 0.3% at $14,305. (Reporting by Pratima Desai Editing by David Goodman, Kirsten Donovan)
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