A carving of the Janaran Falls.
Janaran Falls is a waterfall on the planet Betazed. It's one of William Riker's and Deanna Troi's (and Thomas Rikers) favorite views on Betazed.
Thomas Riker once made a carving of it in metal to give as a gift to Deanna Troi using nothing but a phaser. (TNG: "Second Chances")