This is a relatively new material for making engagement rings out of. It is a darker metal than platinum but very, very strong. It is also hypoallergenic. While it isn’t nearly as rare as gold or platinum, it is more difficult to craft as it is so hard so the price usually reflects this.
The website www.titaniumera.com/uk/index.html will illustrate the darkness of the metal and how it looks with a diamond. It certainly is different and if your girl is looking for a darker metal, it could be a great option.