Certificate of authenticity · Verification code KGEGKXPEVA · Version 1
Ho disegnato un'immagine della grotta
Tim Berresheim
| Inventory number | TB22/P 292 |
|---|---|
| Year | 2022 |
| Technique | Harz und Pigmente auf Papier |
| 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
d131d1caf1bfcb73fa9b141da6b5aff1436331bc791ea3cd3051c98d60474970- Signature (Ed25519, Base64)
NFRFjL3rw73BmHrWO+O0IrVBHOYkEjDWe2d1Os04CCwHJhYinaEw68/dy3LZCXpYbCwxlTqRKgUWBS4Dgw5UBg==- Artist’s public key
0a347c3cdcf869a45213eb6eea4e65d4f60adb6d1fe7d9be59eace1f04584708- SHA-256 of the main image
15bba87bc90813214b719b68b244d07863da8c89d8c1ebe5a4c3fe5efd0e0db8
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.