Titanium rings available through Titanim-jewelry.com are all designed to hold center stones measuring about 6.0mm. For diamonds this would be about .80ct - .90ct. You have a choice of natural colored grey titanium or the exotic black titanium rings. Because they hold larger diamonds they are perfect for engagement rings! Most of these titanium rings have thicker top sections allowing for the larger stones. Most titanium engagement rings being manufactured today hold small stones, but now you are able to showcase a much larger gemstone with our new titanium rings. Please contact us for a competitive quote on a beautiful diamond that will fit perfectly. Or use your imagination and choose a colored gemstone These rings come set with a cubic zirconia at no extra charge if you do not wish to purchase a diamond or gemstone.