not sure on the age, but these links may help
petina is a sticking point with many collectors, and dealers, if you plan to keep it shine it up or what ever, if you're thinking of selling it, leave it as is, most collectors prefere it that way
http://pages.tias.com/7401/PictPage/1920671158.html
http://www.antiqueresources.com/arti...opperdate.html
http://www.tace.com/links/index.html?cat=2
