P3D Re: Brass, again, for antique viewers

[roberts@xxxxxxxxxxxxxxxxx (John W Roberts)]

>Date: Sun, 1 Feb 1998 21:07:20 -0700
>From: Bob Wier <wier@xxxxxxxxxxxxxxxxx>
>Subject: P3D Brass, again, for antique viewers

>Here's something from another list I'm on - this is rather
>surprising as the first item is the same as the formula to CAUSE
>tarnish on new brass parts, which was verified here as being effective.
>I guess it all depends on whether the part is immersed or suspended
>above in the vapor (!).

>...Brass Cleaner (for dirt and mild tarnish)

>        1 part water
>        1 part household ammonia
>combine ingredients is a glass container. Insert item, let soak, then
>remove and rub with cloth and clean.  Seal with paste wax or lacquer.

Perhaps those with tarnished brass could just make a trade with the people
who have pieces of new brass that they want to tarnish. :-)

Could it be that the ammonia just facilitates the reaction, without being 
consumed in the process? Anyone know the chemical formula for brass tarnish? 
(If ammonia vapors can cause it, it wouldn't be a sulfur compound like silver
tarnish.)

John R


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