[Jewelry making - Article 00070] - Re: [Orchid] Cyanide question [was: broken drill bit]

[Peter W. Rowe]

========[ Invite a Friend - http://www.ganoksin.com/invite.htm  ]========

>        Hi Peter and all, I am not a chemist or a scientist and after
>     your reply about cyanides I started to reflect on. I sometimes use
>     potassium cyanide to clean gold from oxydation, mostly on chains. I
>     have never think that this substance can attack gold or other
>     metals. May be you was talking about another cyanide or maybe I have
>     never let metal enough time into it to note it. Would you please
>     give more infos about it. 


Vincent,

    Either Potassium or Sodium Cyanide solutions will dissolve gold,
    silver, or copper.  Not as rapidly as strong acids will, but still,
    quickly enough to be notable.  For it to go faster, use an electric
    current to "strip" the gold into the solution.  Like that, cyanides
    can be used to quickly and efficiently etch patterns into gold or
    silver in the same way that acids are used as etchants, and the etch
    is often smoother and more even than with acids.  Using cyanides as an
    etchant does mean you need more secure masks, as the strong alkaline
    nature of cyanide solutions will break down many of the materials
    that can be used as masking agents when etching with acid.  The effect
    of just dipping gold items into cyanide is not so visibly obvious as
    an etching one, since it's slow, and there is no bubbling or obvious
    action.  The oxides are dissolved more obviously, but the gold is also
    being removed.  It doesn't so quickly make it all dull, so you may
    not be aware that metal is being dissolved.   But it is.  Take a piece
    of thin gold sheet metal or wire, and leave it in a cyanide solution
    overnight.  Then use a micrometer on it the next day, and you'll see
    it will have been slightly reduced in thickness.  If the solution is
    hot, it acts much more quickly. 

Peter Rowe


____________________________________________________________________
T h e   O r c h i d   L i s t
Open Electronic Forum for Jewelry Manufacturing Methods and Procedures
____________________________________________________________________
Orchid FAQ:
~ http://www.ganoksin.com/orchid/faq.htm
Orchid Archives:
~ http://www.ganoksin.com/orchid/archive
Orchid Galleries:
~ http://www.ganoksin.com/orchid/gallery.htm
Invite a Friend:
~ http://www.ganoksin.com/invite.htm
____________________________________________________________________
Tips From The Jeweler's Bench - Article Archive
~ http://www.ganoksin.com/borisat/tip_sear.htm
The Jeweler's Selected Bibliography List
~ http://www.ganoksin.com/jewelry-books
Buy Orchid Jewelry:
~ http://www.ganoksin.com/shop
____________________________________________________________________
-Unsubscribe:
-Email: orchid-request AT ganoksin.com Body=unsubscribe subject=blank
____________________________________________________________________