Dear Linda-;
    "Muriatic" is merely a name for dilute hydrocloric acid. The only shell thing it should be used for is to loosen or disolve calcious things that tend to attach to some shells. And, even then, it's better to put it on with a fine brush over a wash stand
so you can rinse often. It is commercially used to clean concrete.
        Hope this helps,
            Art
Linda Bush wrote:

> Hi, Ross and the rest of you!
>
> An old book I have, by Walter  Freeman Webb, says to dip the shellsin hot muriatic acid (yuck, that's dangerous) and then plunce them into ice cold water.   Needless to say, I have never tried it, so I don't know if it works or not.  But I do have some of those "polished" shells, which I obtained a long time ago from curio shops.
>
> Cheers,
> Linda