Bitcoin ends dramatic week with 20% slump followed by recovery

Amid warnings of bubbles and infernos, currency hits new high of $16,660, crashes, then recovers to $15,350 as London closed

Bitcoin rounded off a week of frenzied investor speculation with a day of whipsaw trading that knocked nearly 20% off its value at one point, but still left the cryptocurrency changing hands at more than $15,000 (11,000).

The currency, which was likened to Dante's Inferno by one senior banker this week, rocketed to a new high of $16,660 overnight before slumping to $13,482 by midday on Friday. As the London markets were closing, bitcoin had recovered some of its losses to trade at $15,350 - having started the week at $10,875 and the year at $966.