Beautiful Emerald Green Sheffield or Sheffield like 1800's art glass pedestal oil lamp with duplex burner. Pretty sure it is a Sheffield even though it is not marked. It is 27 inches tall to the top of the chimney.
Beautiful etched shade, absolutely beautiful. Due to its age there are some signs of age, including a small spot on the base of the lamp where the black finish is missing. An easy repair if you wish to do it.