Bitcoin and its kin start New Year with a bang

Bitcoin and most other large cryptocurrencies rose on Tuesday, carrying their 2017 momentum into the new year, and gaining one more high-profile investor Peter Thiel.

The prices rose after news that Mr. Thiel's venture-capital firm Founders Fund had invested heavily in Bitcoin, a nine-year-old virtual currency. Prices as of Tuesday afternoon were up 11.5% to $14,950, after ending 2017 at about $14,000, according to research site CoinDesk.

Founders Fund bought between $15 million and $20 million worth of bitcoin in 2017, investments that are now worth hundreds of millions, people familiar with the matter told The Wall Street Journal. Even though the investments were made earlier, the news was greeted by bitcoin investors as further vindication that their pick is gaining a lasting, institutional following.

Mr. Thiel was a co-founder of PayPal, which in some respects was founded with a vision similar to that of bitcoin -- to create a new kind of digital currency. In 2014, Mr. Thiel said in an interview that he was "unfairly biased against bitcoin" because PayPal hadn't succeeded at creating a new currency, instead becoming a large payment network.

This past October though, Mr. Thiel said people were "underestimating" bitcoin.

Tuesday's crypto market's gains were spread broadly. Eighteen of the 20 largest currencies were rising on Tuesday, the first trading day of the year for traditional capital markets. XRP, also called Ripple, was up about 7%, trading around $2.36. With a total market value of $92 billion, it is the second-most valued cryptocurrency, behind only bitcoin.

XRP rose sharply into the year-end, rising about 50% on Friday alone. XRP's gains have been driven by news coming out of Ripple, which launched the token in 2012 and has been building the project as a cross-border trading tool for banks.

Prices of another cryptocurrency, Ethereum, rose about 12% to $866, after hitting a record high on Tuesday of $904. That is double where it was on Dec. 10 and triple its value on Nov. 1.