LONDON: A non-fungible token (NFT) of a digital artwork called a "CryptoPunk" was sold for $11.8 million on Thursday, according to a tweet by auction house Sotheby's.

The NFT - a blockchain-based asset which certifies ownership of a digital object - was sold as part of the Sotheby's online auction "Natively Digital: A Curated NFT Sale", which runs from June 3-10 and features work by 27 digital artists.

CryptoPunks are a series of 10,000 unique pixel-art characters made by Larva Labs in 2017. The individual one sold by Sotheby's -- "CryptoPunk #7523" -- is of the sought-after Alien variety with blue-green skin, and wearing a medical mask.

Two other Alien CryptoPunk NFTs have sold for more than $7 million each in previous sales. Anyone can view the artworks the NFTs represent, but only the buyer has the official status of being the owner.

For each purchase, the NFT is sent to the buyer's cryptocurrency wallet; no physical artwork changes hands.