Nokta FoRs Gold, a Gold Cube, 2 Keene Sluices and Lord only knows how many pans....not to mention a load of other gear my wife still doesn't know about!
It looks to me like a ‘cataphote’ reflector (commonly known as ‘cat’s eyes’) as used for better visibility at night for things such as traffic and railroad signs, as well as for advertising purposes.
A number of patents have been granted for particular designs, including to Percy Shaw in 1927 and Evan Bone in 1932