A very true fact about men's birthstone rings is that, the design of the ring and more specifically the size of the gem would be influenced by each specific birthstone. For example, a mens sapphire birthstone ring would be quite expensive if you choose to set a large 10x8mm or 11x9mm natural sapphire in the ring. This would be true even if the sapphire you choose is of a medium grade (quality). On the other hand, if you were looking at the February birthstone for a mens birthstone ring, the gemstone would be an amethyst. This gem would be modestly priced even in sizes that are as large as 14x10mm. All this is something that your jeweler should advise you about but, just keep it in mind. Many jewelers are not willing to take the time and effort to discuss solutions and options with buyers.