You may have wondered what Rottweiler colors are possible and if there are color combinations to avoid that don't adhere to the breed standard.
AKC breed standard: "Always black with rust to mahogany markings. The demarcation between black and rust is to be clearly defined."
The Rottweiler color mahogany is a deep, rich color that looks quite astonishing due to the reddish-brown look.
The Rottweiler with the color black and rust is actually pretty similar to the one with mahogany, with the difference being that it's a tad lighter. This color is quite common for the Rottweiler and Doberman.
The so-called "rare Rottweiler colors" are not desirable at all. It's important to understand that most of these are crossbreeds and/or carry gene defects which often come with the associated health issues.