Art Deco "Gorham" match box holder/ashtray made of offers copper/Bronze,

Vintage Art Deco Gorham signed, dated and numbered hotel match box holder ashtray. Beautiful Shield with "WH" or "HW" initials inside shield. I really wanted to clean and polish but I'm told not to remove original patina. We believe its from Washington D.C. dated 1923 with art deco design. Could this be from the 'Wardman Hotel" or Hotel Washington" both hotels date during 1923? The patina is very dark and has green oxidation as shown in pictures, this piece is very heavy for a match box holder. I think this would make a great addition to any collection. I have not seen one like offers this, only a few similar ones.
measurements: 5 3/4 long, 4 1/4 wide, 3 1/2 tall approx.