A data filtering and visualization tool to map ancient metal and stone deposits, as they've been recorded in the online "gazeteer" Pleiades (https://pleiades.stoa.org). This is currently an exploratory tool: it makes no claims to comprehensive or exhaustive information on the topic, in part because it is limited by the mines and sources of minerals presented by Pleiades. The word "gazeteer" is critical, then. Users confuse this with comprehensive data at their own peril.

By way of explaining color coding, I've tried to make them as intuitive as possible—red for iron, grey for silver, green for copper (when oxidized), and so forth. I can't explain purple for tin: grey was already in use, I suppose. Users are welcome to change color in the code itself (it's near the end of the python code).

As far as dates go, future iterations may allow users to filter by date. The current code does not. All dates are presented togther and labeled according to the conventions adopted in Pleiades. I was not able to find a full list of date codes on the website, but the tabular data does provide descriptions along with codes like "C" and "A" (which are clear enough—"classical" and "archaic").

A count of the mines and quarries reveals the following breakdown.

1. "archaic" = A: 223
2. "classical" = C: 497
3. "hellenistic-republican" = H: 1316
4. "roman" = R: 7126
5. "late-antique" = L: 2888

Pleiades combines these codes to show overlap among periods (thus AC or RL).