Bitcoin Ordinals to bridge Ethereum NFTs with the launch of BRC-721E

cointelegraph.com:

Bitcoin Ordinals are the latest layer-2 solution enabling decentralized storage of digital art on the Bitcoin blockchain. Ordinals will now allow users to migrate their Ethereum ERC-721-based nonfungible tokens (NFTs) to the Bitcoin blockchain with the launch of the BRC-721E standard.

The BRC-721E standard was jointly launched by the Ordinals market — an Ordinals-based marketplace — and the Bitcoin Miladys NFT collection. The new BRC-721E standard enables the conversion of immutable, verifiable ERC-721 NFTs to Ordinals. Initially, metadata is not stored on-chain, but users can store a lower-quality preview image and include a reference to the Ether (ETH) burn in the raw image data.

Our #Bitcoin Ordinals bridge is now liveIn collaboration with @OrdinalsMarket_ & @xverseAppBridge: https://t.co/T9UhTNVp4WNew token standard: https://t.co/YDERWSPPfaMarketplace: https://t.co/UTzAzBsO9PLet’s take over #Bitcoin! pic.twitter.com/Ki9dGfxuuJ

The migration process starts by burning the ERC-721 NFT with an ETH call function. The burning of the NFT is an irreversible process and acts as an on-chain inscription method. To claim the ETH burn on Bitcoin, the user must inscribe valid BRC-721E data, after which the bridged NFT will appear on a custom Ordinals market collection page with complete metadata.

The indexers that check the burned NFT data inscriptions ensure that a token has no more than one valid inscription and that the genesis address matches the burn transaction call data.

Related: Bitcoin Ordinals surpass 10M inscriptions as creator Rodarmor steps down

The Ordinals market claimed the fundamental principles of BRC-721E and the flexibility of the indexers allow for the protocol to evolve over time, despite the fact that