The story of the pearl 
 
Clams live very deeply. He finds himself an area to be protected from the dangers of the sea. And it does not leave. It rarely opens up its shells. It is only on rainy days. And at this moment, sometimes a grain of sand escapes into it. The oyster perceives this as a danger and covers the grain of sand with a secretion. It continues for a very long time to cover the sand grain with secretion. Until he feels safe. And in the end, he turns the particle of dust which he fears into a precious pearl.