A good match, perhaps from the Zürich area...

[magnesium]

I'm delighted that this manuscript is proving useful. In my cursory review of the Swiss archives, I have generally found that early 15th-century manuscripts with origins in either Zurich or Basel can yield pretty good matches, though the quality of the match varies. The distinctively angular Ls and Bs seem like a consistent tradition, and some of the other quirks, like the "cz" ligature, pop up pretty frequently. For example, see the fifth line here: You are not allowed to view links. Register or Login to view.