RK17 A00104 is a Pillar Dollar found during the archaeological excavation of the Rooswijk in 2017. The coin was minted in Mexico City in 1737.
In 2016 Dutch and British archaeologists undertook a survey on the site of the Dutch East Indiaman Rooswijk which showed it was at high risk. To address this a team has come together from Historic England and the Dutch Cultural Heritage Agency (RCE) to undertake an archaeological excavation in summer 2017. Follow this project on social media using #Rooswijk1740
You can read the press release about the project here: https://culturalheritageagency.nl/en/news/dutch-and-british-archaeologists-to-excavate-300-year-old-shipwreck-before-it-is-destroyed-by-t