The Treasury building has a dome over each corner stairwell of the building and a three section skylit dome over the central west double stairwell.
The domes of the Treasury building were installed in the 1860's to provide natural light to the stairwells beneath them. Of the 5 domes, the west dome is the most elaborately detailed.
In 2005, the dome was restored to its original appearance when elevators, place in the center of the stairwells in 1910 were dismantled and concrete slabs that blacked-out the skylights during WWII were removed.
The restoration of the west dome in 2005 involved applying gold leaf to each of the coffer ornament rosettes which had been painted over when the elevators were installed in 1910.
The restoration of the west dome has been completed. A remaining aspect of the project is completing the restoration of the stairwell handrail and balustrade where elevators were removed from the center core of the two stairwells.