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 closedBitcoin 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