Mother-of-Pearl (Dr Damien Leech, UWE Bristol – Centre for Fine Print Research)

“The Purple Flattop Shell is a really common find on South UK beaches, known for the distinctive purple patterning. However, general wear and tear tends to pull off the upper layers, revealing an even more striking colour beneath. This nacreous layer, more commonly known as mother-of-pearl, displays a range of structural colours can be seen most prominently when at an angle to the observing eye (hence how out of focus it is!).”

– another great example of structural colour in nature! Interestingly, this effect was understood over 100 years ago for mother-of-pearl: https://www.sciencedirect.com/science/article/abs/pii/S0016003217910452