BEIJING, July 10 (Reuters) - Copper prices in London and
Shanghai extended gains for a second day on Tuesday, with
investors lured to buy low after a trade war-fuelled sell-off
last week.
    The United States on Friday slapped tariffs on $34 billion
of goods from top metals consumer China, which responded in
kind. Fears that the trade spat could dampen demand for
industrial metals had weighed on copper prices.
    "It's already maybe a bit oversold," said Helen Lau, an
analyst, Argonaut Securities in Hong Kong. The prospect of
strikes by labour unions in South America has "dragged on a bit
too long," which is also supporting prices, she added.
    Labour negotiations at BHP Billiton Plc's
Escondida copper mine in Chile, the world's largest, are
entering the final three weeks before a 30-month contract
expires at the end of July.
    * LME COPPER: Three-month copper on the London Metal
Exchange was up 0.4 percent at $6,418 a tonne, as of
0414 GMT, extending a 1.7-percent gain from the previous
session. The metal lost more than 5 percent last week.
    * SHFE COPPER: The most-traded September copper contract on
the Shanghai Futures Exchange gained 0.6 percent to
reach 49,850 yuan ($7,549.48) a tonne by the mid-session
    * ZINC: There was no such respite for Shanghai zinc
, however. The metal fell as much as 2.3 percent to
21,725 yuan a tonne, having dropped 5.3 percent last week on
trade war fears and expectations of higher supply.
    * ZINC FUNDAMENTALS: "A lot of zinc concentrate is coming on
line from mines across the world," this year, Lau said, adding
that demand for zinc in steel galvanising in China was seeing "a
bit of a slowdown." 
    * RUSAL: United Company Rusal, the world's
second-biggest aluminium producer, in May increased aluminium
exports to 197,000 tonnes, up almost threefold from April,
Interfax news agency reported. {nL5N1T72B2]
    * BLOCKCHAIN: Online metal concentrates exchange Open
Mineral is seeking to build a consortium of mining companies and
financial institutions to create a blockchain system for
minerals trading and logistics.