Mauritshuis magenta ink made by P.W. Akkerman pen store in The Hague.
Originally made to celebrate their 100th anniversary, this ink comes in a vintage-style bottle with a narrow neck with a marble stopper, to create a well at the top to aid in filling pens.
The Mauritshuis is an art museum in The Hague in the Netherlands. The museum houses the Royal Cabinet of Paintings which consists of 841 objects, mostly Dutch Golden Age paintings. Originally, the 17th century building was the residence of count John Maurice of Nassau. It is now the property of the government of the Netherlands and is listed in the top 100 Dutch heritage sites. (source: Wikipedia)Ackerman