What happened 

Shares of cryptocurrency stock SOS Limited (SOS -1.74%) jumped as much as 21.7% in trading early on Friday after announcing preliminary six-month results for 2021. Shares fell from their high of the day but were still up 10.1% at 2:15 p.m. EDT. 

So what

Management said that revenue jumped more than 17 times in the first six months of the year to $184.5 million, and gross profit rose from $0.08 million to $17.2 million. However, operating loss was still $20.4 million as stock and legal expenses weighed on results.

Physical Bitcoins on top of a smartphone.

Image source: Getty Images.

Crypto mining was the clear growth driver for SOS Limited with 132.1 Bitcoins (BTC 0.77%) and 1,853.1 Ethereum (ETH 1.50%) mined in the first six months of the year. Mining rates more than doubled in the second quarter of 2021, versus the first quarter. 

Now what

The huge jump in revenue is what investors got excited about today. What we're not seeing yet is profitability, which is what investors should look for in the second half of the year. For now, there's a lot of revenue to be made in the hot market, but to be truly sustainable, investors will want to see the bottom line improve.