After a brief reprieve on Thursday, when most digital currencies finished in the green, all major coins put up losses in U.S. trading hours Friday.

Bitcoin BTCUSD, -0.17% , the world’s largest digital currency, was last changing hands at $6,385.77, down 1.9% since Thursday at 5 p.m. on the Kraken cryptocurrency exchange. It reached an overnight high of $6,621.71.