Certificate of authenticity · Verification code 6RQHN5YZ79 · Version 1
Observattions from a hill - 7
Tim Berresheim
| Inventory number | TB06/E 21/7 |
|---|---|
| Year | 2006 |
| Technique | Risographie |
| Dimensions | 40 × 30 cm |
| Edition | 7/7 |
| Issued | 13.11.2026, 08:07 |
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
ed869cae2c0e0dc75294d0843a905abd0f74d1d4e04e0dcdd0aa4663407394b7- Signature (Ed25519, Base64)
5Ee/q5pK89wNkvG93X84d+Uxz/4EhGDV05k5flmE53sjv7XyhsDMm0u2uMPCzXIDjQl80ikeAG026qx/TI6kDw==- Artist’s public key
0a347c3cdcf869a45213eb6eea4e65d4f60adb6d1fe7d9be59eace1f04584708- SHA-256 of the main image
5dc6955080717b52f407442d8bbf31212928105a1ffb1c3f828f7d38f5696216
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.