What is Black Zirconium? Zirconium, not to be confused with zirconia, is a natural element that has the symbol Zr and the atomic number 40. In its original state, this metal is grayish-white 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. Cool!
In jewelry applications, it is mixed with another metal (usually Hafnium) 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.
Pros: Extremely lightweight.
Cons: If the ring surface is scratched on a hard enough surface, the original white color may be exposed.