I want to present my friend a wedding anniversary ring.My preference is diamond.Please help?

Unless your friend is also your significant other, don’t gift an anniversary band.

Dear Friend,
Diamonds are the hardest natural substance known to mankind. That, along with their brilliance and fire, have made diamonds the quintessential symbol of timeless, enduring love.
Diamond anniversary rings are an expression of continuous love and affection. They are the perfect gifts for those sentimental occasions. To celebrate your engagement, your anniversary, or just another day together, specially chosen diamond rings will be the lifelong symbols of these magical moments.Please go through online, because you will get the detailed information about diamond anniversary rings from there. You will get a number of sites providing valuable information. Recently I searched . It is a marvelous site offering you a fabulous list of services like information, price list, new metals& alloys, new designs, designer collection and lot more. Just have a look on that

Best Wishes
Regards
Tiwar

As Perse said, unless this friend is your spouse, you don’t give diamond rings as anniversary gifts. If you’re keen to give your friend an anniversary gift, perhaps try finding something for the couple, not just one person.