Indeed. Curaçao (Neth. Antilles) still issues coins in exactly that shape and style - the 50 cent coin. See this image of a recent set. Aruba's 50 ct piece is also square but has a modern design. Christian
Right, but there is a reason. The theme of that collector coin was "sculpture"; others in that sort-of-series were about architecture and painting. So the artists Mirjam and Hester Mieras wanted to make every design element of the coin to look like a stone sculpture. That applies to both the Queen's head and the value (the VIJF on the €5 coins and the TIEN on the €10 piece). Odd but appropriate ... Christian
here's 1 modern coin I bought about 10 years ago. Queen Beatrix head looks like a topographical map. I loved this design. ICG 1990 proof-68 DCAM 50 G. KM#214 the reverse side looks like all the 4 queen heads were carved in stone.
here's another thread started called Netherlands. linK: https://www.cointalk.com/threads/netherlands.116210/