Tiffany's does make dog collars, and they are really pretty cheap. I wouldn't use one as a lead, but just for looks and tags they might be safe.
Tiffany Dog tag toggle necklace. - Necklaces - Tiffany & Co.|Home|International|Tiffany,GUCCI,925 Sterling Silver Jewelry Manufacturer & wholesaler
Here's their bracelets.
http://www.ourism.com/index.php?gOo=...6&productname=. These are all so cheap; I wondering if it's one of those knock off sites.