Other industrial metals were also headed for their biggest quarterly fall in several years, down between 20% and 40%.
Many analysts fear further declines in the near term, as central banks push ahead with rapid interest rate rises that will stifle growth.
"We still see metals falling as a recession in the U.S. is fully priced in," said Commerzbank analyst Daniel Briesemann.
Benchmark copper on the London Metal Exchange (LME) was down 1.1% at $8,306 a tonne by 1047 GMT and down 19.9% since the start of April.
Copper fell 19.8% in the first quarter of 2020, when COVID-19 spread worldwide. There has been no other quarterly plunge on that scale since 2011.
Briesemann said copper could slip as low as $7,000-$7,500 in Q3, but prices should rise towards the year-end.
MARKETS: Global stock markets have suffered the worst first half of the year on record. [MKTS/GLOB]
DOLLAR: The dollar is set for its biggest quarterly gain since 2016, making metals priced in the currency costlier for non-U.S. buyers. [USD/]
CHINA: Chinese factory activity rose slightly in June after three months of contraction caused by COVID lockdowns.
JAPAN: Japan's manufacturing output saw its biggest monthly drop in two years in May.
PRICES: LME aluminium was down 0.5% at $2,459.50 a tonne and down almost 30% in Q2; zinc fell 3.2% to $3,252.50 and was 22% lower in Q2; nickel slipped 2% to $23,305 and was down almost 27% in Q2; lead was 0.7% lower at $1,920 and has fallen 20% in Q2; tin rose 0.1% to $26,790 but has plunged 38% in Q2.
The quarterly declines for all five metals were the biggest in at least a decade.
(Reporting by Peter Hobson; Additional reporting by Brijesh Patel in Bengaluru; Editing by Shinjini Ganguli)