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I have a few questions I’m unable to answer about ammonites. I’ve been doing some casual research, but it seems to lead to more confusion on this. I would really appreciate it if anyone could suggest more sites to look at as well. What kind of shell “decoration” is present on ammonites with ammonitic sutures? Was there any “normal” combination of shell and suture mark, or could their shells have any pattern of ridges, knobs, etc.? I’ve been hoping to find a sort of before and after polishing photo/sketch set, showing what shell went with what suture pattern, but have been unable to find anything. While trying to find the photo/sketch, I realized all photos of ammonitic sutures I’d found were of creatures that were involute, the outer whorls almost completely covering the inner. Is this just a coincidence, or were most/all ammonites with ammonitic sutures so involute? Also, did any/some/many/all ammonites with ammonitic sutures have an aptychus? I've been able to find all sorts of information on these features individually, but not on co-incidence, so to speak.