This counter is made from a mineral sold as onyx. Technically, this dimensional onyx is a mineral called banded calcite and it has a different chemistry from the onyx used for jewelry and inlay work. It's every bit as beautiful as true onyx even though it's made from the same mineral travertine is. It's less resilient, softer and more stain-prone than granite, but it has a depth and movement that no other dimensional stone can touch.
Whether you call it onyx or banded calcite, it's a definite show-stopper.