The Star of Thor is a treasure that features in season 3 of Kaitou Joker.
The Star of Thor appears to be a large (roughly the palm of Captain Blue's hand) pear cut reddish pink gemstone that glows slightly.
Before Series Edit
At some point in the past, Captain Blue's grandfather, Captain Black, obtained this legendary treasure. His ship at the time capsized in the Caribbean Sea, and as such the treasure was presumed lost.