I've noticed scrolls are bugged: In my fort where rollers had to be made from conglomerate, I somehow had scrolls that were made of native aluminium and alunite, and I hadn't done any trading. Furthermore, it seems paper quality isn't added to quires and scrolls(which is weird considering paper has a quality), so in general I am assuming books' components are just bugged in general... There's at the least a bug reported where binding books messes with the value: http://www.bay12games.com/dwarves/mantisbt/view.php?id=9409
Also, I just realised the thread title probably needs to say Scrolls vs Codices...
I noticed this as well. My scroll rollers are usually made from green glass. The item description will have two roller materials. The actual green glass and seemingly a random stone type. I am not sure what causes this.
As to what makes a scholar a sage; (the following is based off observations of visiting scholars and my own scholars)
1. Noob scholars are just called scholar.
2. Scholars who have a high skill in any 1 category of academic skills are called that thing. For instance Astronomer.
3.
Dwarves that are called Sage appear to have a high teacher, critical thinking stat, and some other academic skill. Both dwarves that are called sage in my current fort have 11 in teacher, crit think, and logician. I am not sure if it is that specific combo or if the 3rd skill can be anything instead of logician.Edit: I dug out a 42.02 fort because I knew I had a naturalist there. So these are my findings with all available data (15 forts total across 42.02-.04.
SAGE - High Levels of Critical Thinking + Logician or a Medical Skill (so far these skills are the only ones I have seen on a unit with the Sage title, however I suspect that any 2nd skill combined with critical thinking will give you a sage)
SCHOLAR - Low level academic skills
PHILOSOPHER - High Levels of Logician (can be paired with anything else except Critical Thinking since that will produce a Sage or Mathematics since that will produce a Mathematician)
MATHEMATICIAN - High Levels of Mathematics (can be paired with Logician)
HISTORIAN - High Levels of Critical Thinking
ASTRONOMER - High Levels of Astronomy
NATURALIST - High Levels of Tracker
CHEMIST - High Levels of Chemistry
GEOGRAPHER - High Levels of Geography
ENGINEER - High Levels of Optics or Fluid Engineering, can be coupled with Mechanic or Pump Operator.
Medical professions work as always except when coupled with critical thinking since that will produce a sage.