Shanghai base metals close mostly lower; copper down 0.71%, nickel falls 1.67%

The split within Shanghai base metals matters more than the headline decline: nickel's 1.67% drop stands apart from tin's 1.22% gain, suggesting this is metal-specific positioning rather than a uniform macro move. The overnight copper decline tracking the SHFE leg points to a shared driver across sessions, while alumina and aluminium alloy holding small gains hints that the aluminium complex is absorbing the same flow differently. Whether nickel's underperformance and tin's resilience persist into the next session is the open question, along with whether the copper weakness continues to transmit between the domestic and overnight markets.