For example, in ITC Franklin Gothic, the dot over i is square but the diaeresis is made of two round dots: http://tinyurl.com/apq7sc
This does not make sense. Of course the diaeresis dots usually need to be smaller than the i-dot, but should share the same formal characteristics (so they should optically look alike). In the bolder weights of ITC Franklin Gothic, the dieresis is not only of wrong shape but also is too light. Of course in typefaces influenced by calligraphy, the dot over i can safely have a slightly different shape than the dieresis (e.g. in Robert Slimbach’s Arno Pro), but in very regular geometric faces the shapes should be very harmonized.

The placement also tends to be a problem. In some typefaces the dot over i is placed very high (e.g. the Garamond display cuts), but the dieresis (and the dot over other letters such as o or z) can safely be placed lower. But if there is no compelling reason for the i-dot to be placed at a different height, the placement of all diacritics should be harmonized with the placement of the i-dot.

I think you’re missing the ü and Ü, an “u” letter with two little point over it.
Here we call the “diéresis” or “crema”.

In Spanish we need it to mark a difference between “gue” and “güe”, the first one, the U is mute; on the second, you have to pronnounce the U.

Like: guerra (muted U), paragüero (u with sound)

Thank you!

I want your help with a project. I want to make 15 diacrititic marks for the 15 vowel sounds in English, and use them to help little kids learn to read. Please give me a shout!
Chris Bogardus, 828-406-9580

Typography is indeed important! and i just know that fact recently… poor me!

Love your blog and what your are doing. but IMHO your last theme is better. :) Anyway, can i interview you for my website? Email me is the answer is yes

As being another Dane with a love for typography, not being able to use æ, ø & å, when writing texts in more special typography, is a major problem.

Still this is just a small problem though, in comparence to the Czech language. Your article here has really given me a look into the world of diacritical marks. This is especially one of the areas I’ll try to play with and learn from when I start making real fonts instead of just playing with different letters being adjusted to a typeface. I’m actully looking forward to it, thought it’s properly hard work.