Crypto miner Riot Blockchain has tripled its bitcoin production in a year - and is sitting on more than $190 million in coins

• Crypto miner Riot Blockchain said this week it had mined 346% more bitcoin in September this year than last year.
• The company said it currently holds 3,534 bitcoin from its mining operations - roughly $190 million in coins.
• Mining companies "hoarding bitcoin is a game changer," Michael Saylor, CEO of MicroStrategy said in a tweet.

Crypto miner Riot Blockchain tripled its production of bitcoin in September, as demand for all things digital continued to flourish, and is building up a sizeable reserve of coins itself, according to a company press release earlier this week.

The company mined 406 bitcoin in September, marking a 346% increase compared with the same month a year ago. Year to date, the company has produced 2,457 bitcoin, a rise of 236% over the same period last year.

The company, which is publicly listed, said it now holds 3,534 bitcoin - worth around $190.7 million at the current price of roughly $55,000 - but did not say why it was storing them.

Michael Saylor, the CEO of data platform MicroStrategy, which has invested heavily in bitcoin, said the decision was significant in a tweet on Tuesday.

"In September, @RiotBlockchain mined 406 BTC, sold none of its production, and ended the month with 3,534 BTC on its balance sheet. Publicly traded Bitcoin miners aren't selling bitcoin, they are accumulating bitcoin. The game has changed," Saylor tweeted.

Crypto mining is the process where coins like bitcoin are extracted from their blockchains through solving complex mathematical problems that require intense computing power and high levels of energy.

Since the recent exodus of miners from China, which has been steadily clamping down on all aspects of crypto production and ownership, mining activity has increased elsewhere. Riot said it currently has a fleet of around 25,646 mining machines, and said it plans to increase this to more than 27,000 by November.