I've got to agree with Fan here sox4life. I've never understood the whole "promise ring" theory. If you're that sure you are going to marry her why not propose now (I did after 4 months and we've been married for almost 9 years). If you are not ready for that, why not get her some diamond earrings, or diamond studded pendant. Not really anything extravagant but something simple yet elegant. Also, go to a reputable dealer for a better quality, cut and clarity of stone. It also maybe something you can put on layaway.