The Rubaiyat of Omar Khayyam:
1910 T.N. Foulis Maurice Greiffenhagen Miniature Edition

This is a miniature copy. My hand for scale.

It was printed by T. and A. Constable in Edinburgh.

Of particular note is how the year is displayed: MDCCCCX. Now, this is, of course, Roman Numerals. However, the format is not standard. If you put it into a converter it will error out and say invalid. Apparently, MDCCCCX was sometimes used instead of MCMX. This article was how I discovered the strange usage and an example of it. Definitely threw me for a loop when I was trying to date it!