The lowest rank was a simple "von" attached to the family name, without any real title (in Austro-Hungary the "courtesy title" Ritter" = knight was added). That "von" served about the same purpose like the British "Sir" does to this day, though the "von" was usually heriditary. The "von" was attached to the family name by royal letters patent for merits in military, science, arts, industry or economy. Examples are "von Dreyse" or "von Mannlicher". A family of this rank could use a crown with 5 tines/pearls above the monogram, while a Freiherr/Baron was etitled to 7 pearls, a Graf/count to 9.

Quite likely, as the baronial crown looks a bit unusual for a German one in detail. As I wrote, Baden-Baden was populated during the summers by aristocrats and other well to do people from all Europe before WW1. It was called the "Summer capital of Europe" then. Russian nobility even had their own church built there. Nagel & Menz catered to that international clientele.