Dyestuff Citizen Science.

If you have a textile find, it's sometimes possible to extract the dyestuff used for dyeing it. The instruments and technique have been refined more and more over the last decade or two, but there's still a problem: Knowing which dyestuff combination comes from which plant. 

A lot of things will dye some kind of yellow, so if you have yellow, it doesn't mean you know which plant it was. In analysis reports, this can then turn up as "yellow x". There's a similar issue with red, where it's not always known what was the origin of a red dye that was detected.

The Danish National Museum is now going on a citizen science quest to try and find those elusive colour suppliers, and they are looking for dyers willing to collect, document, and send in their dye sample. The project runs until October 2027, which is when all samples should have arrived in Denmark.

If you are interested and would like to know more, you can find it here on the museum's website.