artworks (or contracts for sale) signed via public key crypto

"When an interested buyer decides to buy a copy of the artwork, they send a payment through the platform along with their own public key. The artist then signs a message including data like the purchase price, timestamp, parties involved, and any other data that might be relevant or interesting. Any legal agreements or copyright transfer details can also be included as desired. This is all collected together, signed, and publicly displayed, and voila! Ownership transferred."