Cryptocurrency prices traded lower Monday, unable to hold onto last weeks gains.

Bitcoin, the worlds No. 1 digital currency is trading at $6,261.00, down 3.7% since Sunday at 5 p.m. Eastern Time on the Kraken exchange.

After a volatile few sessions, bitcoin BTCUSD, +4.05% spent the weekend inside $6,300 - $6,600 with weekend trading volume at its lowest level since June 9, according to data from the Bitfinex exchange.

Ricky Li, CEO of cryptocurrency trading and asset management firm Altonomy, said volumes have been particularly light in the altcoin market, the market for smaller coins other than bitcoin. “We are seeing a new low in volumes in the altcoin market this year,” said Li. “The top few [cryptocurrencies by market value] are still the safest space and we are seeing rotation out of them into bitcoin.”

Bitcoin volume data, Bitfinex exchange

After breaking out of the weekend range Monday, bitcoin is testing critical support, that if broken, could open up a significant move lower. “Last week’s decline leaves BTC in a fragile technical position as it attempts to stabilize/base at $6,100-$6,200 support. A break below $6,100 would signal a retest and possible break of $5,800 support with potential risk to $5,000,” wrote Rob Sluymer, technical strategist at Fundstrat Global Advisors.

Monday’s broad-based selloff has pushed the total value of all cryptocurrencies below $200 billion, last at $193.7 billion according to data from CoinMarketCap.

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Major altcoins slip further into the red Monday

Coming off a bounceback week, which saw Ether ETHUSD, +7.02% rise as much as 20% off its low, the second-largest digital currency was giving back significant gains Monday, trading down 12% at $195.09. Litecoin LTCUSD, +4.89% was down 8.5% at $52.21, Ripple’s XRP coin XRPUSD, +3.03% was lower by 3.9% at 27 cents and Bitcoin Cash BCHUSD, +4.76% was off 7.5% at $415.50.

Bitcoin futures ended lower Monday. The Cboe Global Markets Group Inc.’s September contract US:XBTU8 finished the session down 4.8% at $6,217.50, and the CME Group Inc. September contract US:BTCU8 closed down 4.5% at $6,230.

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