Cobalt chrome boasts a beautiful, platinum-like color throughout the ring making it a great, affordable choice if you are trying to pair it with a much more expensive platinum or white gold engagement ring. Cobalt rings will not chip or crack the way harder metals and ceramic can. It is both light-weight (heavier than titanium, but lighter than tungsten) and hypoallergenic - so cobalt is often used in the medical field, especially for hip replacements.. Lifetime size exchanges are included in your Manufacturer's Lifetime Warranty. In case of an emergency, a cobalt wedding band can be removed with a diamond-tip ring cutter.