[Rockhounds] Geology in Progress

[Lawrence Rush]

Thank you Earl! Great answer! Logical and good science! Am I am happy to 
think that water pollution is NOT responsible! These are the best beaches in 
New England, with uncommonly clean surf and sand, a pleasure to visit and 
swim (and collect Magnetite) in!

Thanks to all!

Larry


----- Original Message ----- 
From: "Earl R. Verbeek" <everbeek at ptd.net>
To: <rockhounds at lists.drizzle.com>
Sent: Monday, January 05, 2009 9:28 AM
Subject: Re: [Rockhounds] Geology in Progress


> Hi Nate,
>
> I'm just now getting caught up on a week's worth of e-mail messages and 
> ran
> across yours on flotation methods.  I don't have anything to add right now
> on the commercial aspects of this process, but if you'd like to 
> demonstrate
> it in your own home it's easy to do.  Just get some seltzer water, some
> peanuts, and some raisins.  If you put peanuts and raisins in plain water
> you'll see they both sink -- both are denser than water.  But if you place
> them in seltzer water you'll find that air bubbles adhere to one and not
> the other, so you'll get a neat separation.  I forget whether it's the
> peanuts or the raisins that float, but it's a simple and effective
> classroom demo to use to illustrate the process.
>
> The beauty of such flotation methods is that you don't have to use heavy
> liquids for mineral separations -- those liquids (bromoform, Clerici
> solution, etc.) aren't the most user-friendly chemicals in the lab.
> Instead you can use a liquid that is less dense than any of the minerals
> you hope to separate, but with the proper additives one will float and the
> others sink.
>
>            Cheers-   Earl Verbeek
>
> On Sun, 4 Jan 2009 21:42:06 -0500,  wrote:
>> Pete, et al
>> I did a quick search on "magnetite flotation" and came up with a number
> of
>> hits that were suggestive however most of the references did not permit
>> articles to be downloaded so only brief snippets could be viewed.  Froth
>> flotation methods were mentioned several times and it makes me wonder if
>> the
>> natural froth generated by heavy wave action might preferentially bind to
>> magnetite and enable it to float.  Various polymeric or other chemical
>> additives also seem to be important in flotation mineral processing
>> applications.  It makes me wonder what the effect might be of various
>> impurities in the water near the RI beach that Larry visited.
>>
>> Isn't it amazing where a simple observation can lead?  I'll bet someone
> on
>> the list has some experience in flotation methods and can give us some
>> insight.
>>
>> best regards,
>> Nate Martin
>> Lexington, MA
>>
>
>
> -- 
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