Certificate of authenticity · Verification code 89D4EBFK7B · Version 1
La riunione annuale degli insegnanti di flauto
Tim Berresheim
| Inventory number | TB22/F 378 |
|---|---|
| Year | 2022 |
| Technique | Baryt |
| Dimensions | 60 × 50 cm |
| Edition | unique |
| Issued | 13.11.2026, 08:05 |
Timestamp anchored in Bitcoin, block 975648.
Verification
- …Checksum of the certificate file
- …Artist’s signature
- …Timestamp in Bitcoin
- ·ImageDrop the image file here to compare it with the certificate.
Drop a file here: image, certificate (.json), signature (.sig) or timestamp (.ots). Nothing is uploaded; everything is computed in your browser.
Verification data
- SHA-256 of the certificate file
afdd984e908594b3ac3b10049e68c3eca4307406dc405b7dc23ce32aab49bae3- Signature (Ed25519, Base64)
zFlU9QvuMYM/zK0hJIVBYoXKpWvqczH0v7av3KqbYvw0B4maHvj5uxw0R8ZD7PjUGdX9oEGEFoZnB8i4Hbp8AQ==- Artist’s public key
0a347c3cdcf869a45213eb6eea4e65d4f60adb6d1fe7d9be59eace1f04584708- SHA-256 of the main image
801b483cb854aa493f42f32a39901a64a4c9897cf97bea9ff3e4b84ec4a1ed6e
How to verify this independently of this page: hash the JSON file with SHA-256; the value must match the checksum above. Verify the signature against that checksum with the public key (Ed25519). Check the .ots file together with the JSON file at opentimestamps.org: this proves since when the checksum has been in the Bitcoin blockchain. The proof depends neither on this address nor on the artist, only on certificate, key and blockchain.