We have run into a puzzler that comes from a Wikipedia article on Pope Gregory's various tiaras (see http://en.wikipedia.org/wiki/Papier-m%C3%A2ch%C3%A9_Tiara). The problem is that we wish to determine the primary source document for the following statement in that article: "A new silver papal tiara to replace the destroyed ones was only manufactured in 1820, but the papier-mâché tiara continued in usage for decades afterwards, its lightweight design making it a comfortable alternative to the heavier silver alternative for popes as they aged. It was finally officially retired from usage in 1845, when a new lightweight tiara was manufactured for Pope Gregory XVI."

We assume that the lightweight tiara manufactured in 1845 was not made of papier-mâché, but was instead of lighter weight materials than previous tiaras. In any event, the article does not cite a reference for this 1845 tiara, and we have been utterly unsuccessful in locating such reference. The lone citation in this article, Twining's History of the Crown Jewels of Europe, does not broach this particular topic. We have been able to verify that.