Unobtanium cryptocurrency (UNO) is a digital currency created in 2013, which uses the Proof-of-Work protection method and the SHA-256 consensus algorithm. This cryptocurrency is very popular among miners, as it is combined with Bitcoin mining. Unobtanium cryptocurrency is more secure for users since its blockchain is more complex and fast. The developers of the currency laid the algorithm of 250,000 UNO coins, which, according to their calculations, should be enough for 300 years of mining. This cryptocurrency is unique because it is not subject to inflation. In addition, Unobtanium (UNO) has a number of characteristics that distinguish it among other cryptocurrencies - it is a dedicated community, distribution equity, durability, simplicity, and scarcity. Premine was 0%, lost/stolen coins are not recovered, therefore Unobtanium is considered to be a cryptocurrency with “fair mining”, and scarcity is one of its main characteristics. UNO implemented joint mining with Bitcoin from 600,000 units in May 2015. Combined mining allows Bitcoin miners also to mine UNO. As a result, the security of UNO-blockchain has increased significantly.