When I took these pictures of a former painting supplies store in Mainz, it was the ligated ‘ch’ pair that had caught my eye. Not that it was unusual to keep these two letters (as well as ‘ck’) together. On the contrary, it was pretty much the norm in Germany until deep into the second half of the 20th century — a relic of blackletter, where some ligatures were considered mandatory, and atomic. One can find them in all kinds of letter styles, tightly spaced or truly connected, joined at the bottom, at the top or with an abridged ‘h’ stem, and even in caps.
Ligatures for ‘ch’ and ‘ck’ are not limited to lettering, they were present in metal typefaces, too. Most German releases used to come with them. When browsing specimens lately, I ran across this very ‘ch’ ligature again: “L.Schuler” is not freely lettered, but indeed derived from a typeface: It’s Arkona fett, designed by Karl Klauß and first cast by Genzsch & Heyse in 1935.