Reddit reviews The Glass Magician (The Paper Magician Series, Book 2)

The Paper Magician and The Glass Magician and the first two books in the Paper Magician series, in which nineteen year old Ceony Twill must set aside her disappointment - she wanted to be a Smelter, a metal mage - and learn paper magic instead. But unknown to her, the Folder to whom she's apprenticed happens to be deeply involved in the hunt for dark mages who work with human flesh ...

So far as I can tell, the books aren't marketed as young adult, but they do have a kind of coming of age theme, and - to this point at least - the subject matter would be perfectly acceptable for teens. The writing is sophisticated enough for adults, however.