The Duchess Diamond of the Netherlands belongs to the monarchy of the Netherlands, and appears in the 1987 TV series, in the episode April Gets in Dutch. As the Turtles, April O'Neil and Irma arrive to Amsterdam in the Netherlands, the diamond is put on public display for first time in 50 years.
Two local jewel thieves, Spats Sparkle and Dag, are after it and attempt to steal it and sell it while replacing it with a faked diamond. Shredder and Krang are after the real diamond, to use it when opening a portal between Earth and the Volcanic Asteroid and send the Technodrome through using Krang's "Laser dimension blade".
- April Gets in Dutch (English). TV.Com (1992). Retrieved on May 26, 2017.