I have not abandoned this area of research;  I'm currently in contact with materials suppliers.   

I think you can make sodium carbonate from sodium bicarbonate.  I will look up tomorrow.

You can also simply buy some rochelle salt.
It is not really hard to come by nor is it very expensive.

Another chemist want to comment on the rochelle salt piezoelectricity?

As for sodium carbonate production, I cannot find the link.  So perhaps it is best to acquire sodium carbonate reagent for pool pH equalization.

Not very much to comment on really...
What is there you want to know about it and cannot find?

Piezoelectric effect is always due to the crystalline structure of the material.
Rochelle salt is a Na/K-tatrate, can be made by reacting two ingredients as was
already quite adequately explained in that link provided by AbbaRue, but
can also simply be bought. It is not expensive at all, and should be easy to
order from a shop or website that sells common chemicals.
If you have trouble finding it, you may want to search for its other name
"Seignette salt", or simply "potassium sodium tartrate".
Since it is used in the food industry as a preservative and additive,
you might be able to find it with suppliers of food additives, as E337.

But perhaps it is worth knowing that although it is piezoelectric,
several much more piezoelectrically active materials have been
developed. Quartz is also piezoelectric, as is barium titanate,
and actually there are quite a number of piezoelectric
compound materials that can be made. For a historic perspective
it may be interesting that one of the old 1940s electrophysics
books in my collection very clearly states that rochelle salts
can be used to generate a piezoelectric effect, in more modern
piezo elements barium titanate is used to greater effect. Hehe,
yes, obviously the "modern" relates to the 1940s...
There are even better ones nowadays, but barium titanate is
still used for many if not most piezo uses. Except for the
piezo oscillator components, those are most often quartz.

But remember: piezoelectric effect has to do with pressure differences.
So there need to be pressure differences or kinetic shocks for the
material to produce output.
Just like the pyroelectric effect of tourmaline needs a temperature
difference or constant temperature fluctuations to produce output.
You can make a neat looking cell of piezo material but it won't do
much without input shocks or pressure fluctuations, and similarly
you can make a really neat pyroelectric cell but you'll need to have
a fluctuating heat source to get anything usefull out.

Yes, Hutchison keeps bringing up the Casimir effect.
As a Dutchman, I am of course proud of mr Casimir for discovering
that zpe effect, but I do feel Hutchisons remarks are perhaps
more confusing than usefull.

When you think about it, the casimir effect must be involved in many
other effects. For example, all "vacuum attraction" phenomena can
be interpreted in a Casimir view. Or for another example, the function
of a capacitor can also be interpreted as a form of Casimir effect.
(Perhaps interesting to point out that the first capacitor was also
a Dutch invention, the "Leyden Jar")
I personally think that that is the sort of interpretation we should
seek behind Hutchisons Casimir remarks.
In a sense it is a sort of zpe interpretation. I guess if JH would say
"it is zpe powering the cell" he would immediately be dismissed by
most investors and researchers, but the Casimir effect is well known,
so that will not be dismissed as easily.
But that's only my personal view.
If you have a better one, I'd be happy to hear it.

@sutra  Good to hear you have been experimenting


@all

Can we convert Bis-Beta-carboxyethyl germanium sesquioxide back to free germanium?

I spent some time searching for Rochelle Salt suppliers and the best price I could find is about $25/Kg.
I can get cream of tarter at the bulk barn for $8.80/Kg. That's about 1/3 the cost.
Takes a little time making it up though.
The recipe says 200g. of cream of tarter produces about 210g of Rochelle salt, thats another bonus.