Role of Tellurium in oxidation

Hi, I was wondering if I could get some help from the group
concerning Tellurium. I am trying to help a customer that has a
question about the functional roll of Tellurium in Black Max, the
silver oxidizer we sell. I learned a lot from searching the archives
like how rare it is and how it turns your breath a foul order, but
didn’t see anything about what role it plays in the chemistry. Any
ideas? Any help would be greatly appreciated.

Thanks
Mark L. Nelson

Gold tellurides: Au_2 Te_3, Au_3 Te_5, and AuTe_2 are black
compounds, no oxygen is involved.

M Chapman

Sulfur, selenium and tellurium are similar in the way they react with
other elements. So the tellurium is basically acting like the sulfur
in liver of sulfur. Along with oxygen they are a member of the group
of elements called Chalcogens You might read this
Chalcogen - Wikipedia for some more insight to why
they react in a similar way with other elements.

Jim

Tellurium It’s a component in Griffiths Silver black, I don’t know
the chemistry behind it, but it does blacken non-tarnishing silvers.

Regards Charles A.

It is said to be the origin of the phrase ‘Stinking Rich’ as the
miner who smelled worst had mined the most gold.

As far as I know the dust from the mine contained tellurium or the
fumes emitted from smelting ores were absorbed by miners in certain
mining areas.

The foul breath and body odours being the consequence.

It is well worth while scrolling through the Wikipedia pages.

Along with oxygen they are a member of the group of elements
called Chalcogens You might read this 

Interesting reading, yes. Much more to the point and more
fundamental might be this, though:

That’s how almost all patinas work, in one fashion or another. Also
rust and hemoglobin and all sorts of things.

On the same vein. I’ve used selenium (photo developing toner) to
blacken silver. We very rarely see anyone recommending selenium.
which leads me to wonder it is dangerous or just offers no
appreciable advantage over LOS or tellurium based solutions. I find
the tellurium based solutions easier to use on both gold and silver
when compared to LOS. is there a difference in durability of the
finish, or is LOS used so prevalently because you have more control
of the degree of darkening? I find LOS fussy. I only use either in
recessed areas give no surface treatment isgoing to withstand
application to a fully exposed component. Are the new nano ceramics
appreciably more durable when compared to traditional "black"
surface treatments?