Can anyone identify the BG number for this California Fractional Gold Half Dollar? An approximate value would also be helpful.
I am unable to find anything on line about the BG however I did stumble across this article that you might be interested in seeing. http://www.ngccoin.com/news/ViewArticle.aspx?NewsletterNewsArticleID=1378
I looked through all of them and your coin does not match anything listed. Your coin is similar to what a combination obv BG 420 and rev BG 408 would be, except for one thing. The BG 420 only has 11 stars on it and yours has 13 stars. By no means take this as gospel but I can only conclude that your coin is probably a fake. If you'd like to read all for yourself, you can do so here - http://users.scronline.com/lockem/ Just click on - Denominated California Gold Guide on the right hand side once you get there.
There are many replicas of California gold. It even talks about it in the redbook. I have a replica 50 cent gold.