100% Original Good Pricing Fast Shipping 8mm Men's Black Tungsten Carbide Laser Engraved Greek Key Design Ring Big SALE Brand: Accents Kingdom ® SKU: rts074 Material: Tungsten Carbide Style: Comfort Fit Finish: Black Coating W/ Greek Key Laser Engraving. Width: 8mm All Tungsten Carbide we offer use Nickel binder. NO Cobalt. We use Tungsten Carbide 857 About Tungsten Carbide Tungsten Carbide is space age alloy, it is the hardest of all metals: about 10 times harder than 18K gold, 5 times hard than tool steel, and 4 time harder than titanium. Rated between 8 and 9 on the Mohs scale the hardest of which is diamond being rated a 10. Due to their extreme hardness, Tungsten Carbide Jewelry will hold their shape and shine longer than any jewelry on the market. Reflection with a sparkling luster.