Capitalization

Q. Hi. I’m trying to find out if you should always initial cap a subsequent reference of a proper noun when the full name is not used. The specific term in question is Rock of Cashel. On second reference, where this is referred to as “the rock,” I don’t want to cap it, but the author of the piece does. I looked at the Q&A and CMOS but didn’t see a specific reference so I felt better to ask.

A. Chicago style doesn’t cap the generic term, but sometimes an author has reason to. For instance, if locals call this popular landmark “the Rock,” or if the document refers to other kinds of rock, it might seem odd or confusing to lowercase it. I wouldn’t fight about it.

[This answer relies on the 17th edition of CMOS (2017) unless otherwise noted.]