Polmine.

Polmine, written PolMine on its site, was a Bitcoin mining poolMining poolA group of miners who share the work of finding blocks and split the rewards, so each gets paid steadily instead of rarely. from Poland, which the Bitcoin Wiki calls the first Polish pool. It opened on 14 June 2011 and found its first block two days later. By January 2014 it called itself the largest and longest-running cryptocurrency pool in the country. Its site was in Polish and named no company or people, only its “administrators”. mempool.space can identify its blocks only from April 2013, and credits it with 1,290 from then until June 2015. In August 2014, its busiest month, it found about 3.5% of all blocks.

At first Polmine shared out each block’s reward by how much work each miner had done. From December 2011 it paid by PPS, pay per share: a set amount for every piece of work a miner sent. From June 2012 it used SMPPS, a kind of PPS in which the pool never pays out more than it has earned. Each Polmine block’s first transaction paid the reward to the pool’s own address, and the pool paid its miners from there. These are payments to the pool’s miners, separate from the transactions confirmed inside the block. The same work also mined Namecoin, and by 2014 Polmine ran pools for Litecoin and Dogecoin too.

On 11 December 2014 Polmine stopped handing out work to its miners, for reasons it said were beyond its control, while it rebuilt its server, which it warned could take a while. Four days later it asked miners to take all their coins out of the pool, saying it could no longer be responsible for money left there; coins still there after another week would be moved to an exchange. mempool.space credits it with blocks again from March 2015, until its last, on 7 June 2015. Its site still showed the December notice in June 2016, and no announcement that the pool had closed was found.