" When the commissionaire had gone, Holmes took up the stone and held it against the light. “It’s a bonny thing,” said he. “Just see how it glints and sparkles. Of course it is a nucleus and focus of crime. Every good stone is. They are the devil’s pet baits. In the larger and older jewels every facet may stand for a bloody deed. "

― Arthur Conan Doyle , The Adventures of Sherlock Holmes (Sherlock Holmes, #3)