8mm Black Matte Finish u0026amp; Thin Blue Groove Tungsten Carbide RingnClassic, Weighty and Durable, excellent scratch resistant performancenGreat workmanship on brushed matte surface and high polish smooth inner face, bring you both the Elegance and Comfort.nNew King Will box is online now, the new and the original will be sent randomly. King Willu0026#39;s jewelry box helps to store the ring much safer and longer.nIf you have any question, please post into u0026#34;Customer Questions u0026amp; Answersu0026#34; at the bottom of this page.nTungsten is a very hard and dense metal with hardness between 8.5 and 9.5 on the Mohs hardness scale (Diamonds are a 10 - the highest). Its density, similar to that of gold, allows tungsten to be used in jewelry as an alternative to gold or platinum. Tungsten carbide is about 10 times harder than 18K Gold, four times harder than titanium, twice as hard as steel, and is the only rare and exotic metal that can be permanently polished. Your Tungsten Carbide ring will maintain it's virtually scratch resistant polished finish for decades when subject to normal wear. All rings come with a free ring Box.