Sentence:  <WSD>Aventurin</WSD> or <WSD>avanturin</WSD> glass was formerly made only in the Island of Murano, near Venice, but is now prepared throughout Germany, Italy, Austria, and France. It is a brown glass mass in which crystalline spangles of metallic copper according to w:Friedrich Wöhler 
Meaning of the word marked with <WSD> tags:  A kind of brownish glass containing gold-coloured spangles.