An Elanin singer stone was a little stone that emitted sounds when it was touched by a living being. It would not react with artificial lifeforms, such as Soong-type androids. It was said that it sang a different song for every person. Doctor Pulaski owned one.
The Dreman girl After her planet was saved and her memory of the encounter with the crew of the USS Enterprise-D was erased, Data gave an Elanin singer stone as a present to Sarjenka. (TNG: "Pen Pals")