The largest open image search for ancient coins — museum holdings, auction records, and catalogue data in one place, free.
Search the archive →A sighting is one recorded appearance of a coin — an auction listing, a museum specimen, a catalogue entry. The same physical coin can surface multiple times over decades. 305k+ sightings means 305k+ documented moments, not 305k unique coins.
A type is the design template: a specific emperor, denomination, mint, and iconography combination. Thousands of sightings can belong to one type. 139k+ types is the taxonomy — the index of what was made, not just what's been seen.
Every image is downloaded and stored on our servers, not just linked. When auction house pages go offline or museums restructure their URLs, the image stays in the archive. Links die. Files don't.
Two embedding models — DINOv2 and SigLIP2 — turn each coin image into four numeric fingerprints: obverse and reverse for each model. Search compares your photo against all of them across the full corpus.
Data flows in from Nomisma SPARQL queries, Europeana's API, Corpus Nummorum, Smithsonian collections, and Wikidata — all normalized into one schema.
Plot coin production across the ancient world, filtered by date range and material. See where coins were made and how production shifted across centuries — from 600 BC through the late Roman period.
Syllogeum is built and maintained independently by kauzmic, out of frustration that numismatic image search is still bad in 2026. Not affiliated with any institution. Not a credentialed numismatist. A meaningful portion of the code was written with AI assistance (Claude), and that's disclosed upfront.
The name comes from sylloge (Greek: συλλογή), meaning collection or anthology — as in Sylloge Nummorum Graecorum, the long-running series of scholarly coin catalogues.