I did online research on Tungsten Carbide because I had never heard of it before.  All I wanted was a cheap ring for myself that was different from what most people have (gold).  The reviews for this type of ring were excellent, so I made the purchase.  It's a great fit, and I even got a thumbs-up from my daughter who wrinkles her nose at everything.  HOWEVER, the picture isn't accurate.  The light-gray edges are actually silver, and the large gray portion is dark gray - almost black. Still, if I were to lose this ring, I'd go straight to Amazon and the seller to buy a replacement.  I'm more than satisfied with my purchase.