sentences:  Prong setting engagement rings are sometimes referred to as Tiffany setting rings, although this is a trademarked term specifically used to describe prong setting rings sold by Tiffany & Co. A 2017 $19 million lawsuit confirmed the exclusive right of Tiffany & Co. to utilize the term "Tiffany" within the jewelry sales industry.The head can be handmade, cast or die struck, and it is made from some type of precious metal, such as gold, silver and platinum.Heads used to prong set a gemstone come in a variety of sizes and shapes, depending on the shape of the gemstone, the size of the gemstone, or whether or not the gemstone is faceted or cabochon shaped.