The appetite for digital currencies keeps on rising, with their total market value breaking a new record high.

The digital currency market rose above $300 billion for the first time on Sunday evening, according to industry website coinmerketcap.com. By 9:00 a.m. London time on Monday morning the total market capitalization had reached $304,628,469,227. This came as the most prominent cryptocurrency, bitcoin, passed the $9,600 threshold earlier on Monday and Ethereum reached a new all-time high.

Speaking to CNBC, Frank Holmes, the chief executive officer at U.S. Global Investors, said it was difficult to say which digital coin would survive in the current market, but added that more people will learn to trust them as time passes.

"What bitcoin has done, it has woken up everybody to the power of the blockchain technology (the underlying ledger that supports bitcoin), like emails woke everyone up to the internet. At the beginning people didn't trust the internet," he noted.

"So we don't know who's going to survive. We saw Google being surpass Yahoo – how this will evolve I don't know," Holmes told CNBC Monday.

This rapid rise of bitcoin and its rivals has sparked fierce debate over the future of digital currency. Jamie Dimon, the CEO of JPMorgan, has been vocal about the risks of investing in digital currencies, which are not regulated. He warned last month that those "stupid" enough to buy bitcoin will "pay the price for it."

On the other hand, there are those who see benefits in digital currencies. Hans Redeker, global head of foreign exchange strategy at Morgan Stanley, told CNBC that they can become an important tool for monetary policy.