This always looks to me like it should have something to do with bulls, but I can't work out what the aet- would mean. Now I don't want to unduly cramp Mr Chabon's creativity, but it does seem ill formed: he's taken the phrase aetas aurea "Golden Age" and put aetas into its stem form aetat-. However, this more naturally yields a meaning "age-golden", headed by the second element in Latin as in English. For the intended meaning, a straightforward Latin-based word would be 'auraeval/aureval' (with standard variants as for 'primaeval', 'mediaeval').
This always looks to me like it should have something to do with bulls, but I can't work out what the aet- would mean. Now I don't want to unduly cramp Mr Chabon's creativity, but it does seem ill formed: he's taken the phrase aetas aurea "Golden Age" and put aetas into its stem form aetat-. However, this more naturally yields a meaning "age-golden", headed by the second element in Latin as in English. For the intended meaning, a straightforward Latin-based word would be 'auraeval/aureval' (with standard variants as for 'primaeval', 'mediaeval').