From somewhere around the beginning of the 20th century to well into the 1950's, many fountain pens were made with nibs of glass rather than gold or steel. Few have survived to this day as they were generally either budget pens (such as the Spors models imported from prewar Japan) or made during the wars in then resource-constrained Europe.
Despite many previous years of fountain pen use and collecting, I only learn of the existence of glass nibbed fountain pens in 2016. Since then I have collected what I believe to be the cream of the crop, and also made several myself. A handful of sampled are presented below.
Click any image below to see the full sized version, or the link in the description to go to a review.