Tungsten is the hardest metal on the planet. Tungsten rings will never scratch or bend. These rings retail for up to $380.00 in every jewelry store in America. Mk Diamonds sells Tungsten rings for $40.00 apiece. There are several styles to choose from. Sizes start at 10 to 15. MK Diamonds also has Tungsten & 18kt. gold inlaid rings for $100.00, these rings retail for up to $600.00.