Small porcelain hanging lamp.
Cap is really entirely made of white porcelain.
The ceiling cap is also made of stonework.
You can adjust the length as desired when hanging. You then cut the thread to the correct length. You can of course also decide to tie a loop in the thread. That depends on how neatly you want the light to hang.
Cord and fitting are from a later date.
Vintage pendant lamp, shows normal traces of use.