Indium

Most of the metals around us perform their various important tasks silently and in what is perhaps an understated manner. Even when put under stress, the vast majority make no sound and we are often unaware of the huge forces that they withstand, particularly in the instances of towering skyscrapers or vast container ships. Indium, however, behaves quite differently and in not such a discrete manner; bending this rod of indium will emit a strange gritty, cracking, creaking sound, as a result of the microscopic crystals (that all metals are composed of) grating against one another. This behaviour is most commonly associated with tin, a metal that makes a similar sound when deformed, resulting in the phenomenon often being termed “tin cry”. Both indium and tin, therefore, are rare examples of a metal expressing its discomfort as we shape it to our needs.