The heptagonal shape of the 20p and 50p make them much easier to distinguish from other coins by both sight and touch. I can see the different coins in a heap,

The heptagonal shape of the 20p and 50p make them much easier to distinguish from other coins by both sight and touch. I can see the different coins in a heap, and I feel the difference even through gloves. The copper and gold-coloured Euro coins all look very similar.