What did Ostian script look like?

Question

What did Ostian script look like? I've seen some drawings in Origin of the Serif and I'd like to learn more. But when I tried googling I wasn't able to find anything: all I got were false positives.

The example on Figure 212 of Catich's book shows a Roman majuscule A and N, which are described as Ostian inscriptions of the year 75. Both are in the Vatican Lapidary Museum.

Compared to Trajan, the height-width ratio of the letters is smaller. The right leg of the A is very thick, with a very long exit serif.

Answer 1

There is no such thing as "Ostian script". Ostia is known for having been the source of a relatively large number of well-preserved Latin inscriptions (one is shown below). These inscriptions show the same variety of different Latin letters found at Rome itself and in other places within the Roman Empire. Latin inscriptions vary, as one might expect, because each stone cutter had their own style

Answer 2

Ostia was a Roman port, possibly the first of their colonies. As such, the script should have been based on the Latin alphabet, which itself appears to have been derived from the Etruscan script.

Looking at graffiti found in the ruins there was a fair amount of variability in writing of Latin characters.