Local sand

Another close look at sand; collected this time from the beach at the end of our road. Yesterday's sand from the Kalahari consisted almost entirely of broken down rock. Today's is a much more complex mixture. There are some rock fragments but also lot of broken sea shells as well as that curse of our times a micro-particle or two of green plastic. 
Much of the sea shell material will have come from the faeces of the local Eider ducks. They eat mussels and other molluscs as well as crabs and swallow them whole. They are then thoroughly crushed and broken up in the muscular gizzard before traversing the length of the alimentary canal and back into the outside world.