Industria Rotterdam was a Dutch manufacturer that produced lamps from 1920 to 2011. This company is unique because they didn't focus on mass production, but we're customization specialists, unlike their Eindhoven competitor Philips. Later the company was called Industria Technical Lighting.
The company started in 1920 in the Rotterdam district of Kralingen, at the Wollefoppenstraat no. 69-71. The company called itself a brass and bronze foundry. They became famous because of their unique marine bronze.
The strength of Industria Rotterdam was that the company was flexible. If things went less well in the industrial lightning, or ship's lighting, then there was the interior lighting, and if things went less, there was the street lighting.
On my website about ship lamps you can find much more information about this manufacturer:
Machine working Light
Industria Rotterdam has also sold machine work lamps.
Kandem presumably/possibly produces the copper/brass/steel lamp below because it shows strong similarities with the Kandem model 971. It is possible that Industria Rotterdam had these lamps made by Kandem under their label.
The use of different materials is unique to the example with copper shade; the reflector is made of copper, one arm is made of brass, one arm is made of steel, and the foot is made of brass and steel. The other one has brass arms and an enamel hood.
Below are some examples of Industria Rotterdam industrial lighting.