Gold suffered its biggest one-day drop in nearly four years Wednesday, raising questions about whether a torrid rally driven by anxiety over President Trump’s trade policies can continue.

Shares of gold mining stocks Barrick Gold ( GOLD -4.43%), Newmont Mining ( NEM -2.58%), Gold Fields ( GFI -4.85%), and AngloGold Ashanti ( AU -5.98%) were all down today, falling 4.6%, 2.6%, 6%, and 5.1%, respectively.

Gold retreated after topping $3,500 an ounce for the first time as traders booked profit following a nearly 10% rally this month.