Found It: Chic Brass Napkin Rings (from the Hardware Store)
My friend recently sent me a photo of these gorgeous napkin rings from Nopi, Ottolenghi's London brasserie. I immediately became obsessed and had to have them. Since simple is usually hard to find I Googled brass ring and omitted the word napkin. Brass napkin ring brought up some super ornate offerings.
You can find these 1 1/2 solid brass rings on Amazon.