Even if you don't read the article, and even if (like me) you don't particularly care about coin collecting, you should still scroll to the bottom for the cool photos showing how the designs became more abstract over time.
100% this. Really trippy abstraction path over time. Reminds me of how Picasso's style evolved over his career (his early output is amazingly realistic, but his style shifted over time to inform his much-better-known abstract works later in his life).
Mondrian has an interesting path from trees to straight lines and basic colours.