Hi Tim,
First, everything that looks like gold on Aurum knives is gold. Further it is the type of gold that is used on watches and is very hard to resist ware.
The black that Aurum used was plated black chrome and actually harder than the stainless blade itself. The black that Buck uses currently is the "cold blue" that gunsmiths use and is not so tough----so be cautious. You can't really clean off the black but you can alter the character of the black. For example, instead of being a velvet black, it may change to a gray-black. This isn't necessarily bad but be aware that it may happen if one gets heavy-handed with the polishing or buff it on a wheel.
Despite the metals, one needs to be cautions and clean only when there is actually a need for it.
Back to the gold-----
It is very hard and rugged but do not try to remove a deep scratch.
unless you have the touch of a surgeon. You can successfully clean the surfaces to remove surface haze and restore its original condition.
The product "NEVR-DULL" (George Brasch, Co., Inc.), and "EVERBRITE" (Blue Coral, Inc.) are similar and use cotton wadding to deliver their chemistry---a kind of sponge that holds all of the things that do the job. The cotton also give the product some physical pass and resiliency for the polishing action. Other variation of the basic chemistry without the cotton look like tooth paste so you have to furnish your own cloth. Cotton wadding products deliver both a mechanical cleaning/polishing and also a mild chemical one.
The fundamental issue with a "do every metal polisher" is that for any metal, there are added components that are not really being utilized.
In general there are several basic components all of these many products have in common. The relative individual amounts may vary.
When you open a container of "NEVR-DULL" or "EVERBRITE" you can smell what seems to be mineral spirits and that is exactly what it is. It is sometimes called Stoddard solvent. It is essentially the same thing you buy at Home Depot to thin oil base paints. This acts like a degrease to help remove oils and fingerprints. After you break the seal on the container, some or most of it will slowly evaporate but you can add it back. It still works fairly well even when the wadding is dry.
Some other formulas add a bit of isopropyl alcohol for much the same reason but also to dissolve some of the other added chemicals.
Isopropyl alcohol (like in your bathroom), some ammonium hydroxide (like under your kitchen sink) as a cleaner and blue dye is essentially the formula of Windex window cleaner.)
The very mild mechanical polishing action comes from silica powder as fine as face powder. (Silica, silicon dioxide, is what sand this is except this is EXTREMELY fine----less than the size of a red blood cell. This is why it polishes without removing much metal.
There is usually oxalic acid to remove rust. Some formulations contain a bit of ammonia hydroxide for copper based metals.
Most of these formulas have been around since WW II. For a more aggressive cleaner, they increase the coarseness of the silica.
It is important to use caution and deliver the pressure as uniformly to the knife surface as possible while staying out of the black areas.
Sam,
