Where this collection is
Coverage
Four separate numbers. Having a helper does not mean the collection is fully on-chain.
Contracts
Look up a token
Why permanence matters, and why twin your art
An NFT is a token, not the picture
On Stacks, most NFT contracts store a number and a link, not the artwork. The picture lives wherever the link points. If that place disappears or is changed, the token still exists but the picture is gone or different.
How art goes missing
- A website shuts down or moves. The Stacks Art links used by Bitcoin Birds and several other collections now return an ordinary web page instead of the art.
- IPFS content nobody keeps. IPFS names a file by its fingerprint, which lets you check you got the right file. It does not keep the file online: it stays reachable only while at least one computer chooses to host it.
- The owner repoints it. Unless a collection’s metadata is frozen, the contract owner can change what every token’s link says.
What “on-chain” means here
A twin stores the file’s bytes in Stacks transactions, inside the Xtrata contract. There is no link left to break: the picture is part of the chain’s history, which is anchored to Bitcoin and held by every full node. It costs a small fee per file, paid once.
How a twin works
Before anything is inscribed, the helper records a fingerprint of every token’s art in a public record, and it only accepts a twin that matches. A twin and its original are tied one to one, as two sides of the same token: one side is with its holder, the other is in escrow in the helper, and the holder can swap sides whenever they like. Nothing about the original is changed or moved.
Why twin your art
- It survives a dead link, a vanished host or a repointed contract. The picture no longer depends on anyone’s server.
- Anyone can fund a twin, and funding gives no claim on the original. A holder, an artist or a community can protect a whole collection, as was done for Bitcoin Birds.
- Anyone can check it: the twin’s hash must match the public record, and the record’s hash is on-chain.
- It is reversible. The holder can swap back to the original NFT at any time.
What a twin does not do
It does not repair the original contract’s link, change who owns what, or make an NFT worth more. It is a backup, not an investment. Not financial advice.
Before you sign anything
- Never send an NFT straight to the helper contract. Use the swap button on this page or the original page. A direct transfer can strand the token.
- This collection's source has its own marketplace. Unlist an original before swapping it in; a listed original is refused.
- Forever Twins create a permanent on-chain counterpart. They do not repair the original collection's off-chain art or pointer. Not financial advice. Always verify contract addresses before signing.