I recently was gifted a box of Brigham pipes from someone on eBay who bought one of my pipes. The one in this particular write up is the fourth one down which is a 429 Author shape.
I pulled the pipe apart and did my usual cleaning which entails the bowl, shank and lightly sanding it for some contrast. Then I went at the stem. I did my Oxi-Clean and Magic Eraser to the stem and then used the micro mesh pads. When I finished I noticed that the stem was still brownish in spots. So I went out to the shop and dug out my Black Box from when I had my black car. I used it exactly the same way you use it on your car following every step. The first step involves the scratch remover and the second step is the black carnauba wax. I just dabbed it all over the stem and let it sit until it turned to a gray haze. The next set of pics shows the stem covered in the black wax. The final step is to buff it up. As you can see from the pics it covers the brown pretty well. And of course a pic of the final pipe cleaned, waxed and back together. Another happy Brigham.