Earl Brunner on sat 13 dec 03
Chrome is more dangerous in some forms than others, but you probably
still should use caution with it. Potassium dichromate (are you sure
it's bi- not di?) is nastier than most I believe. (I know you said you
understood the high toxicity of potassium dichromate) My understanding
is that you can absorb it through your skin and it is REALLY BAD for
you. I have heard that under the right/wrong conditions it can be
highly reactive and even start a fire.
Having said all of that, once fired it's probably not any more dangerous
that other forms of chrome. I'm ready to be told different though.
-----Original Message-----
From: Clayart [mailto:CLAYART@LSV.CERAMICS.ORG] On Behalf Of sandra
torres
Sent: Saturday, December 13, 2003 7:04 PM
To: CLAYART@LSV.CERAMICS.ORG
Subject: Potassium Dichromate toxicity
Hello,
I understand the high toxicity of potassium bichromate
when raw. However, I would like to know if anybody
knows if this turns food safe after fire. I've been
experimenting with "watercolor on porcelain", using
different sulphates (mainly cobalt, which is food
safe) and potassium bichromate. The process is to
bisque (cone06) the piece, then color it with the
sulphates (that color the clay body). Rebisque the
piece to cone 06 and then glaze it to cone 10.
Is it safe (potassium bichromate) if the inside is
glazed, even if there is some crazing?
Also, does anybody know where to find the book on
Watercolors on Porcelein by Arne Asse?
thank you
sandra torres
=====
Sandra Torres Benavides
27 E. Arrellaga Apt. B
Santa Barbara, CA.
USA 93101
(805) 965 7031
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sandra torres on sat 13 dec 03
Hello,
I understand the high toxicity of potassium bichromate
when raw. However, I would like to know if anybody
knows if this turns food safe after fire. I've been
experimenting with "watercolor on porcelain", using
different sulphates (mainly cobalt, which is food
safe) and potassium bichromate. The process is to
bisque (cone06) the piece, then color it with the
sulphates (that color the clay body). Rebisque the
piece to cone 06 and then glaze it to cone 10.
Is it safe (potassium bichromate) if the inside is
glazed, even if there is some crazing?
Also, does anybody know where to find the book on
Watercolors on Porcelein by Arne Asse?
thank you
sandra torres
=====
Sandra Torres Benavides
27 E. Arrellaga Apt. B
Santa Barbara, CA.
USA 93101
(805) 965 7031
__________________________________
Do you Yahoo!?
New Yahoo! Photos - easier uploading and sharing.
http://photos.yahoo.com/
Butch Welch on sun 14 dec 03
The msds for the product. I would pay special attention to the route of
entry to the body section, it is listed as a carcinogen. In the reactivity
data: Thermal decomposition of potassium dichromate may release toxic and/or
hazardous gases.
A hint to the wise is sufficient. One can handle hazardous material with the
proper safety equipment and knowledge.
http://patapsco.nist.gov/srmcatalog/msds/935a-MSDS.pdf
Barbara Kobler on mon 15 dec 03
Re: Sandra Torress inquiry:
I fume all the nasties BUT I use a full face and eye covering respirator/ventilator, wear a cap, gloves, cotton scarf on neck, long sleeves and cover all body parts when I open the hot kiln and insert the fuming agents. Also I only fume with the outside door (next to kiln) wide open with a fan blowing across the kiln towards outdoors.
These chemicals such as you mentioned as well as sodium sulfates, chlorides, etc are very toxic and absorbed through the skin and inhalation when fuming. I love em, but protect yourself. When painting on these chemicals I don't use the full face respirator, but a smaller one, but wear gloves and long sleeve shirt.
Barbara Kobler http://www.claywoman.net
Ron Roy on thu 18 dec 03
Hi Sandra,
Potassium bichromate is a powerful animal carcinogen. I don't know if
chrome is a danger on ware when used with acid foods - depends on what is
over it - like a stable glaze I suppose - there is bound to be some on the
surface from the fuming - the burning question is - how much is too much?
This is a quote from Mononas book - "Some experts think all chrome compouds
can cause cancer.)
RR.
>I understand the high toxicity of potassium bichromate
>when raw. However, I would like to know if anybody
>knows if this turns food safe after fire. I've been
>experimenting with "watercolor on porcelain", using
>different sulphates (mainly cobalt, which is food
>safe) and potassium bichromate. The process is to
>bisque (cone06) the piece, then color it with the
>sulphates (that color the clay body). Rebisque the
>piece to cone 06 and then glaze it to cone 10.
>
>Is it safe (potassium bichromate) if the inside is
>glazed, even if there is some crazing?
>
>Also, does anybody know where to find the book on
>Watercolors on Porcelein by Arne Asse?
>
>thank you
>
>sandra torres
Ron Roy
RR#4
15084 Little Lake Road
Brighton, Ontario
Canada
K0K 1H0
Phone: 613-475-9544
Fax: 613-475-3513
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