Gold, silver, and copper tumbled on Friday, dragging South African mining stocks sharply lower and sending the FTSE/JSE All Share Index down as much as 4.2 percent, the steepest drop among global markets in April, Bloomberg reported.

Major miners, including Valterra Platinum Ltd., Northam Platinum Holdings Ltd., and Anglogold Ashanti Plc, each fell more than 12 percent as precious metals experienced their largest decline in years. The retreat came after recent weeks of gains that had lifted South African equities to record highs.

Gold, which earlier this week had surged above 5,500 US dollars an ounce, fell below 5,000 US dollars by Friday. Investor concern over a weakening US dollar and shifts in American economic policy had helped propel the earlier rally.

Despite Friday’s selloff, the FTSE/JSE All Share Index is still up approximately 3.6 percent since January and is on track for its eleventh consecutive monthly gain, Bloomberg noted, marking the longest streak on record.