A rare case has emerged of a miner successfully mining a block on the Bitcoin network using a very small device. A solo miner overcame odds described as about a once-in-300-years event and took about 3.128 BTC as a reward.

On April 9 (local time), blockchain media outlet The Block reported that the miner successfully mined block 944,306 using CKPool's solo mining software. The miner received a total of 3.128 BTC, or about $220,000, including a 3.125 BTC block subsidy and 0.003 BTC in fees.

The case is drawing attention because it was achieved with extremely low hashpower. CKPool developer Con Kolivas (콘 콜리바스) said on social media, "Congratulations to the miner who solved a solo block with about 70 TH equipment." He added, "A miner of this size has about a 1-in-100,000 chance of finding a block per day, about a once-in-300-years event."

Seventy TH is similar to the performance of a single Bitmain Antminer S17 released in 2019. Given that the Bitcoin network's estimated total hashrate stood at about 1.02 ZH/s as of April 9, the miner's share is only about 0.0000069 percent. That is effectively negligible compared with the tens of EH/s hashrate of large mining companies.

CKPool, where the mining took place, does not split rewards in the way typical mining pools do. Rather than combining hashpower and distributing earnings, individual miners effectively target blocks on their own and take most of the reward if they succeed. The barrier to entry is low because participants can join without building their own infrastructure, but the odds of success are extremely low.

The case reflects the characteristics of that structure. The miner joined network competition with small equipment but secured the entire block reward with a single success.

Similar cases have also continued recently. Last week, another solo miner using CKPool successfully mined block 943,411 and received about $210,000. The daily probability of success for a miner of that size was estimated at about 1 in 28,000 at the time.

Earlier, in September last year, there was a case of a miner breaking through odds of about once in 100 years to receive a $350,000 reward. In December, another case was reported in which a miner overcame odds of about once in 82 years to secure $280,000.

More recently, cases of solo mining using managed or leased hashpower have been increasing, but finding a block with very small equipment like this remains extremely rare. The industry views solo mining's share of the overall network as negligible, but sees it as a method that continues to be chosen by those willing to accept low odds in pursuit of large rewards.