Billions of dollars were knocked off the market caps of both companies, whose revenues are heavily leveraged towards copper, as copper prices slumped to six-year lows below $6,300 per tonne on Tuesday afternoon.
Glencore shares closed for the day at £2.306, down 6.87%, while in New York, Freeport shares lost as much as 7.8% on an intraday basis as trading got under way in New York on Tuesday.
The sell-off takes Glencore shares to their lowest level since the producer-trader listed in London in 2011, while Freeport’s New York-listed shares dropped to their lowest level since 2009, with both stocks falling below previous multi-years lows seen in January in the midst of the last major sell-off in copper.
Glencore was the worst-performing stock in the FTSE 100 on Tuesday, and the second most-actively traded. Other copper miners – including First Quantum, Antofagasta and Anglo American – also posted losses of several percentage points in London.