What is Black Zirconium? Zirconium has the symbol Zr and the atomic number 40. This metal is silver-grey and very similar to Titanium in that it is lightweight, is skin-friendly (no nickel), and is primarily used in nuclear reactors due to its high heat and corrosion resistance.
In jewelry applications, it is mixed with another metal to create a more pliable, yet still very durable, alloy. After the ring is milled, it is then heated and the exposed portion of the metal oxidizes black, creating a black surface layer and what is aptly named Black Zirconium. This black layer is much harder than raw zirconium, but it is very thin. Unlike oxidized silver and black rhodium, this layer does not rub off over time. It is also more durable than black-coated rings, such as black tungsten.