The price of bitcoin tumbled sharply Friday in Asia, wiping one-fourth of its market value in the past 24 hours alone, as a wave of selling hit the broader cryptocurrency market just before the Christmas holiday weekend.
Bitcoin recently traded at $12,500, according to research site CoinDesk. The notoriously volatile digital currency started December at about $10,000 and traded close to $20,000 this past weekend, but has been in retreat since.
From its recent peak, the virtual currency has lost about $121 billion of its total market value in less than a week, or more than twice the market cap of Tesla.
It wasn't the only currency feeling the pain. Many so-called "altcoins"--shorthand for alternative versions of bitcoin--also declined. And of the 31 digital currencies that have at least a $1 billion market value, 29 were recently down, according to data provider CoinMarketCap.
Ether, the second-biggest digital currency by market value, dropped 26% over the past 24 hours. Another currency called litecoin was down 32%. Its creator, Charlie Lee, said earlier this week that he was selling all his holdings of the currency. Litecoin, whose price hit an all-time high of $375 on Tuesday, recently traded at $229.
Mr. Lee, a former Google engineer who created litecoin in 2011, also warned on Twitter that litecoin was getting "so much mainstream exposure" and that "every crypto bull run I've seen has been followed by a bear cycle."
Digital currencies exploded into the mainstream this year, garnering attention for huge price gains as well as significant swings and drawing scores of investors around the world. The market's price moves starkly contrast with how most traditional asset classes have fared so far this year, such as stocks and bonds, where volatility has been relatively low.
Bitcoin has fallen more than 30% over the past four days, its fifth such decline of that magnitude this year, according to Charlie Bilello, director of research at Pension Partners, an investment-advisory firm in New York. In the prior four instances, it took Bitcoin an average of 38 days to hit a new high.
Bitcoin trading volumes in recent months have been driven to a large extent by investors in South Korea, Japan and other parts of Asia, where digital currencies have gained greater recognition. Rising interest from institutional investors and Wall Street firms have also helped legitimize the currency and contributed to bitcoin's big gains.
Bitcoin futures prices on Cboe Global Markets and CME Group, both of which started trading the contracts earlier this month, were both more than 10% lower on Friday. They were recently pricing in a lower value for the digital currency in the first quarter of 2018 than its current value, a state known in futures markets as "backwardation" and a potentially bearish sign.
A popular alternative currency called Bitcoin Cash has also fallen 40% over the past 24 hours, according to CoinMarketCap. The bitcoin offshoot climbed in value earlier in the week after Coinbase, which operates one of the world's largest cryptocurrency trading platforms, said its users would be able to trade the currency on its systems.
Coinbase, however, has so far had to intermittently halt trading due to insufficient liquidity. The company is also investigating allegations that some of its insiders or their family and friends could have traded Bitcoin Cash ahead of its launch plans.
One outlier is ripple, the third largest digital currency by market value. It has surged 30% in the past 24 hours.
The explosive growth in cryptocurrencies has drawn plenty of skeptics, including central banks, government officials, top bankers and others who think bitcoin is in a bubble that won't end well when it bursts. The Daily Show, a popular late-night, satirical program, ran a segment last week investigating the market's rapid rise.
"There is no way all these people buying cryptocurrencies have any idea what the hell they're investing in," The Daily Show correspondent Ronny Chieng said on the show.
Paul Vigna contributed to this article.
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