Regarding your request for the name of a good jewelry glossary I hope
you won’t think it presumptuous of me to recommend one by one of your
countrymen ! I am refering to : Glossario Gemologico by Percio de
Moraes Branco, Editora da Universidade, Porto Alegre, l984. I picked
up my copy in the Casino Atlantico Mall in a small bookstore when I
was last there several years ago. While it is primarily focused on
Gemological terms there is a lot of great jewelry oriented data also.
Page 134 has a killer graph showing alloys for various colors of 18 K
gold ( 18 colors ! )
I’ll bet that the Gemological Institute in Belo Horizonte will also
have this and other good reference works. Ciao for now, Ron at Mills
Gem, Los Osos, CA.