This clay was made from mud stone and sand from Watchet Bay, in North Devon UK. This is the most geologically similar place to Mars on Earth!
A team from the University of Leicester and the Open University, working on a complex study of the red planet, have found that a type of rock found on Mars bears remarkable similarity to the geology of Watchet in West Somerset. More info here.
We visited Watchet to source some sand and mudstone, and we have turned it into clay, which is being used to make clay plates for our Martian house.