France, Oct. 30 -- An art gallery in Paris is showing and selling things callednon-fungible tokens of digital art. Basically, the buyer gets a code for his money, and that code gives him unique individual access to a work of art. Will NFTs, as the codes are called, become the next big thing in the art world, or are they just a speculative tool to make money - or both?

Gaspard Tertrais discovered the world of cryptocultureduring the first Covid lockdown in the spring of 2019, when he was sitting at home in the western city of Angers, looking for a way to invest the money he was saving by not going out drinking with his friends.

He bought his first NFT when coded access to digital art first started attracting the attention of investors at...