Riot Platforms ( RIOT ) shares rose 5% pre-market after the bitcoin (BTC) mining company unexpectedly posted a third-quarter profit on record revenue.

Net income was $104.5 million, or 26 cents per diluted share, compared with a loss of $154.4 million, or 54 cents, the year before. The company had been expected to post a 12 cent-a-share loss, according to Zacks Equity Research.

Revenue more than doubled to $180.2 million from the year-earlier quarter, driven mainly by a $93 million increase in bitcoin mining revenue, the company said.  Riot mined 1,406 bitcoin during the quarter at an average cost of $46,324 per coin.

The revenue gain at Riot, one of the first mining companies to report, was fueled mainly by a bitcoin price that rose 6.4% in the quarter and greater operational capacity. The company recorded a $133 million mark-to-market gain on its bitcoin holdings, currently 19,287 BTC valued at roughly $2.2 billion as of Sept. 30.

The Castle Rock, Colorado company, which develops and operates large-scale data centers, also announced the initiation of 112 megawatts of core and shell development at its Corsicana, Texas data center campus, following land acquisition and design completion milestones.

CEO Jason Les said these developments mark a pivotal step toward transforming Riot into a large-scale, multifaceted data center operator leveraging its land and power assets.

Riot held 19,287 bitcoin — 3,300 are held as collateral — valued at roughly $2.2 billion as of Sept. 30.

UPDATE (Oct. 31, 09:50 UTC): Adds revenue drivers, mark-to-market  in fourth paragraph.