A photograph captured in a unique moment that welcomes us to one of the most beautiful buildings in the city of Barcelona. La Pedrera. Black & White Moment Collection, where the protagonists are the composition and the contrast to transport the viewer to that very instant. The collection starts with an original B&W photograph and continue with a 2nd edition of 10 hand-signed photographs, followed by a 3rd edition for each photograph, minted using an ERC721 smart contract on the Ethereum blockchain. Collection migrated from Polygon POS (Chain ID 137), first to Polygon ZkEVM (Chain ID 1101) in March 2024 and then to Ethereum (Chain ID 1) in February 2025. In September 2025, the collection has been migrated to the second version of NFTs on Ethereum. Same photos, but improved NFTs with the correction of minting errors; The image field was added to the metadata and the properties field was changed to attributes to comply with the ERC721 metadata standard; Addition of the Chain ID and Token ID as well as the minting date to identify the NFT on the blockchain and authenticate the artwork. Regarding the structure of the metadata: The Token ID of each NFT contains information about the edition and the photograph that certifies this NFT. Example: Token ID 2210 informs us that this is copy 2 of the SOS (B&W) 2nd Edition. Some NFTs TokenID ends on 1 or maybe 2. This means that the NFT has been reminted due to an error in the first mint. The erroneous NFT and the previous version has been sent to the burn address (0x000000000000000000000000000000000000dEaD). Important Recommendation: For the long-term survival of this NFT, you should keep multiple exact copies of the metadata file and the PNG file of the photo. This allows you to pin them yourself on the decentralized IPFS protocol or authenticate the NFT in case of deterioration of platform infrastructure or IPFS itself.
