The Pilot/Observer badge was instituted in August 1935, early examples are of the highest quality and the materials used, throughout its manufactured lifetime varied from nickel silver to aluminium to zinc.
This badge is finished with a silvered eagle and gilded wreath. The eagle is often found in frosted silver with polished highlights. Later badges used silver wash over the zinc base metal, then being lacquered to protect the finish.
Not that many manufacturers were licensed to make this badge; the following is a list of these that are known to the author: