A Gorlan prayer stick is an extremely rare artifact, but has no real value as an antique (except, perhaps, to students of archaeology such as Jean-Luc Picard).
Captain Picard was in the possession of a Gorlan prayer stick and kept it in his quarters aboard the USS Enterprise-D. He traded a bottle of very old Saurian brandy for the artifact. He later gave the prayer stick to Jason Vigo as a parting gift. (TNG: "Bloodlines")
It seems likely that the Gorlan prayer stick originates from the Gorlan, whose existence as of yet has only been confirmed for the mirror universe.