By Peter von Brackel, pp. 129, 178-179, I estimate it's manufactured at the beginning of the 20th century, most probably in Janstein or Inwald glassworks.
Diameter ca 105mm (ca 4"), height ca 41mm (ca 1 5/8"). Excellent original condition with subtle signs of wear adequate to the age of this paperweight. The item "RARE, ANTIQUE BOHEMIAN GLASS PAPERWEIGHT" is in sale since Tuesday, June 11, 2019.This item is in the category "Pottery & Glass\Glass\Art Glass\Paperweights". The seller is "mkord" and is located in Zabrze. This item can be shipped worldwide.