58COIN.

58COIN, a cryptocurrency exchange, launched in 2017. Besides buying and selling coins, it offered contracts that let traders bet on their prices. The exchange also mined bitcoin. In November 2017, a 58COIN researcher said in 2021, it brought in its first Antminer S9 machines and started a private pool for them, which others couldn’t join. Its first block, 493,228, was found on 5 November 2017.

It found 745 blocks, most of them in its first months: about 2.6% of all blocks in December 2017, and about 1% over its whole run. Each block’s first transaction paid the whole reward to a single 58COIN address. That reward is separate from the transactions confirmed inside the block.

Its last block under its own name, 563,915, was found on 20 February 2019, and no closure announcement has been found. 58COIN later said that in 2019 its pool was renamed “58COIN&1THash”. Blocks tagged “1THash&58COIN” appear from 25 August 2019, and mempool.space counts them under 1THash, a pool that Valarhash, a mining company in Chengdu, said was its own.