Bitcoin is closing in on the $6,000 mark for the first time on Friday, trading up 5.1% at $5988 a coin, according to Bloomberg data. The reason for Friday’s sudden spike is unclear. The cryptocurrency had been hovering little changed for most of the morning before suddenly spiking around 10 a.m. ET. Bitcoin has been able to shrug off news of a crackdown in China and regulatory uncertainty around initial coin offerings, a cryptocurrency-based fundraising method. After bottoming out near $2,900 per coin on September 15, it has since rallied.Bitcoin is up more than 500% this year.