A small metal flute from the dead world Kataan, which Jean-Luc Picard learned to play during the lifetime he experienced as the ironweaver Kamin and kept afterwards.
The Ressikan flute comes from the episode The Inner Light. A probe launched from the doomed planet Kataan links itself to Picard's mind, and in twenty-five minutes he lives decades as Kamin of the village of Ressik, raising a family and learning the flute.
When he wakes on the bridge the probe has shut down. Inside it the crew find a box containing the instrument, and Picard discovers that he can still play it.
The flute becomes one of his most valued possessions. In Lessons he plays duets with Commander Nella Daren, with whom he falls in love, and explains to her what it means to him. It is also seen in A Fistful of Datas, where his practice is repeatedly interrupted.