harpists can play harmonics with their left hand by stopping the string with the side of the hand (near the little finger) and plucking with the thumb or finger. up to 3 notes can be played by the left hand. they can play harmonics with the right hand by stopping the string with the upper knuckle of the second finger and plucking with the thumb. only one harmonic note can be played by the right hand. harmonics on the harp sound very beautiful.