[Jewelry making - Article 01007] - Re: [Orchid] Tarnish remover use aluminium foil

[John Burgess]

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    G'day; this is a part repeat of my previous message which contained a
    misleading comment Here is the corrected item; (Thank you Jesse.) 

    /There is no secret in this process of tarnish removal. The tarnish
    on silver items is nearly always due to sulphur combining with the
    surface of the silver, whether from atmosphere, body oils, or
    patinating compounds like the polysulphides. 

    Aluminium foil is attacked by alkalies, like sodium carbonate or
    bicarbonate, with the result that pure 'nascent' hydrogen gas is
    given off./ *From the water solution*./ Normally hydrogen nearly
    always goes around intimately associated with another hydrogen atom,
    and is written H2. But when freshly prepared by this reaction, the
    hydrogen is just single atoms, though it quickly pairs with another H
    atom. So the fresh highly reactive hydrogen r reacts with the
    sulphide molecule of the tarnish to produce minute quantities of
    hydrogen sulphide gas, which bubbles off, leaving pure silver. Thus
    the surface will look slightly rough, but can easily be burnished to
    a bright finish. You will see that no silver is removed in this
    treatment. 

    * */*Sodium carbonate is more reactive than the bicarbonate and the
    aluminium/alkali reaction will proceed more rapidly if the carbonate
    is used.* 

    *. So here endeth the lesson.*

Cheers for now,
John Burgess; johnb AT ts.co.nz of Mapua, Nelson NZ

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