Filtering for Heat Map

I suggest adding a filtering mechanism to the heat map. For example, I'd like to be able to filter out by date (remove ancient coins entries). Would others find this useful? Thanks.

It already kind of exists. You can click and drag on the chart to zoom in on a specific time period

True, TheodorTheTeo. I'd like to view the heatmap without the affects of expansive empires. For example: The Roman Empire and Soviet Union include a great many modern day countries (let's say Latvia), but I don't have a coin from Latvia, but Latvia on the map is colored based on coins from the RE and the USSR.

Okay, now I understand what you mean, that would be neat 👍