GCD is a dataset of coin dies produced in the ancient Greek world from roughly 650 BCE onward (it currently focuses on the Archaic and Classical periods). In the future, it could be expanded to the Greek Hellenistic and Roman worlds.

This data has been put together by digitizing parts of traditional die studies ranging from the early 20th century CE to the present. Its primary datum is the obverse die---that is, the portion of a die-pairing that is nestled inside a metal anvil. While this choice leaves the reverse die---that is, the longer die that is directly hammered upon by the mint worker---unaccounted for, two considerations have guided this choice. First, we wished to attain full coverage as quickly as possible. By recording (a process that often required manual counting) only obverse dies, we covered die studies at a faster rate than we otherwise might have. Second, obverse and reverse dies (outside of some exceptional circumstance) occur in a rough ratio of 1:3. This reflects the fact that reverse dies were subjected to more direct force (hammering by mint workers). While this project takes full coverage as an eventual goal (meaning both obverse and reverse dies)---this dependable relationship between obverse and reverse has meant that our data, while incomplete, is nevertheless meaningful.

Producing this data involves counting the number of obverse dies produced in a particular date range, as recorded in each die study (a common practice in die studies that reflects uncertainty in dating particular coins). Additional metadata is added to those counts to accurately reflect information on the coin denomination, metal, and series classification associated with those dies, along with bibliographic data on the die study itself. Die counts, associated by the author with a period, are then assigned to pre-defined periods of time, 25 years in length. The project is ongoing, and will be updated periodically to reflect the addition of new die studies and the expansion of its scope in time and in space (the next phase will add die studies of Hellenistic states).

There are several supplemental documents that will help to make sense of the data:

• Bibliography.md contains bibliographic information on the die studies used in creating the data.

You need to spin this up in a virtual instance of some kind. For testing you can just run: streamlit run [filename.py], in this case gcd_dash.py.

• Added die studies for: Acanthus Hekatomnid coinage