iandol on thu 22 may 03
Dear Friends,
The test for Lead release described by Janet relies on the dissolution =
of the glaze by any acid which will react with any free or residual Lead =
Oxide. Lead Oxide will dissolve in acetic acid to create Lead Acetate =
which is a soluble substance that has, as a crystalline solid, a =
sweetish taste. Hence, Sugar of Lead.
If the solution from the acid test is mixed with a solution of Sodium or =
Potassium Sulphide, note:: Sulphide... not sulphate!! there will be a =
black precipitate of Lead Sulphide.
Do this in a well ventilated space. If the test solution has not been =
neutralised with Sodium carbonate or ammonium hydroxide you will get =
Hydrogen Sulphide evolving. This is a poisonous anaesthetic gas which =
smells of Rotten Eggs that has the remarkable power of disabling one's =
nasal apparatus. As the concentration rises you stop noticing the stuff. =
Keep on breathing and you will cark it.
Best regards,
Ivor Lewis.
Edouard Bastarache on fri 23 may 03
Hello Ivor,
surfing the Net I have just found a lead/cadmium analyser
at Richoux S.A.'s in Orly, close to Paris, France.
It is very expensive.3510 Euros which close to 4,000 US Dollars
these days.
http://www.cer.richoux.net/default_zone/fr/html/page7054.html
Later,
"Ils sont fous ces Quebecois"
Edouard Bastarache
Irreductible Quebecois
Indomitable Quebeker
Sorel-Tracy
Quebec
edouardb@sorel-tracy.qc.ca
http://sorel-tracy.qc.ca/~edouardb/
http://perso.wanadoo.fr/smart2000/index.htm
----- Original Message -----
From: iandol
To:
Sent: Thursday, May 22, 2003 3:02 AM
Subject: : Lead in the UK (long)
Dear Friends,
The test for Lead release described by Janet relies on the dissolution of
the glaze by any acid which will react with any free or residual Lead Oxide.
Lead Oxide will dissolve in acetic acid to create Lead Acetate which is a
soluble substance that has, as a crystalline solid, a sweetish taste. Hence,
Sugar of Lead.
If the solution from the acid test is mixed with a solution of Sodium or
Potassium Sulphide, note:: Sulphide... not sulphate!! there will be a black
precipitate of Lead Sulphide.
Do this in a well ventilated space. If the test solution has not been
neutralised with Sodium carbonate or ammonium hydroxide you will get
Hydrogen Sulphide evolving. This is a poisonous anaesthetic gas which smells
of Rotten Eggs that has the remarkable power of disabling one's nasal
apparatus. As the concentration rises you stop noticing the stuff. Keep on
breathing and you will cark it.
Best regards,
Ivor Lewis.
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iandol on sat 24 may 03
Dear Edouard Bastarache,
Thanks for this information <<lead/cadmium analyser. It is very expensive.3510 Euros which close to =
4,000 US Dollars.>>>
Given that I do not fire Lead Glazes, thought the first glaze I ever =
made round about 1957 was mixture of Red Lead and Red Clay, 50/50, nor =
do I have any Cadmium stains which would be used at the surface of a pot =
I think I will forego the privilege of owning such a toy.
Best regards,
Ivor Lewis.
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