These were four factory-made lights (two large and two small), with exposed aluminium.
I oxidised the front sections and applied gold-coloured foil to the backs.
The photos show the oxidation and foil application process, starting with the first photo of the original lamp.
This shows the oxidation of the small lamp at two different stages of the process
while this shows the oxidation of the larger lamp
this is a detail of the oxidation
this is a lamp with an oxidised front and a foil-covered back
this shows a lamp installed above an entrance door.
