It is actually a myth that crows and magpies collect shiny objects like keys or pieces of jewellery. Wild adult crows will never collect, hide or store anything other than items of food. Young crows are investigative and curious, so they like to handle objects, peck at them and sometimes hide them. In captivity this would include any small objects, and shiny ones may catch their eye more than dull ones. This is probably how stories of crows stashing shiny objects came about. However, in the wild, young crows play with natural objects like acorn caps or stones.