Pour pomegranate juice into an ice cube tray; Freeze until solid, about 2 hours.
Pop cubes from tray.
In a blender, combine lime juice, liqueur and tequila. Turn Blender to highest speed and gradually drop in all but 2 juice cubes, whirling until slushy.
Dampen rim of serving glass and coat with salt.
Place a pomegranate cube in bottom of each glass. Pour margarita mixture over cube and serve.