A nice and typical Dutch school design ceiling lamp, circa 1920.
 
This lamp is probably from the workshop from "winkelman" (the shop was located on a center of Amsterdam in the famous "Rokin" boulevard).
 
"Winkelman" had a major influence on the lighting in the early 20th century in the Netherlands, this style was also very popular in the international Art -Deco market. This item is in a very good condition and has original patina as well as the original dome.