I think the first description answers the question.  The product contains
citric acid.  Even though citric acid is a weak acid, any acid should be
avoided in cleaning shells - unless there is an ugly stain on a non-glossy
white shell, and you are willing to remove the outermost layer of shell in
order to get rid of the stain.  In that case, citric acid or acetic acid
(vinegar) may be useful.

Paul M.

> ----------
> From:         Conchologists List on behalf of Peter Egerton
> Reply To:     Conchologists List
> Sent:         Wednesday, March 15, 2006 12:53 PM
> To:   [log in to unmask]
> Subject:      Cleaning shells
>
> Hey all,
>
> I just received an email (one of those chain ones with household tips)
> that had the following tips in it:
>
>        Now look what you can do with Alka Seltzer: Clean a toilet.
>        Drop in two Alka Seltzer tablets, wait twenty minutes, brush
>        and flush. The citric acid and effervescent action clean vitreous
>        China.
>        =================================================
>        Clean a vase: To remove a stain from the bottom of a glass vase
>        or cruet, fill with water and drop in two Alka Seltzer tablets.
>        =================================================
>        Polish jewelry: Drop two Alka Seltzer tablets into a glass
>        of water and immerse the jewelry for two minutes.
>        =================================================
>        Clean a thermos bottle: Fill the bottle with water, drop in four
> Alka
>        Seltzer tablets, and let soak for an hour (or longer, if
> necessary).
>        =================================================
>        Unclog a drain: Clear the sink drain by dropping  three Alka
>        Seltzer Tablets down the drain, followed by a cup of Heinz
>        White Vinegar. Wait a few minutes, then run the hot water.
>
> Anyone ever try Alka Seltzer to clean stains and dirt on shells?
>
> Intrigued,
> Peter Egerton
>
>
>
> --
> Peter Egerton, Vancouver, British Columbia, Canada
> - - - - - - - Seashells and Web Publishing - - - - - - - - - -
> Seashell Website:  "Peter's Seashells"
>                (including "Seashells of British Columbia")
>               http://members.shaw.ca/bcshells/index.html
> Email: mailto: [log in to unmask]
>

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