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substitute for manganese?chrome?

updated thu 12 may 05

 

Marcia Selsor on sun 8 may 05


I know manganese is hazardous but what about chrome. I always thought
chrome was worse. It was the one first to be banned from our campus
studio by the hazmat folks.
marcia
On May 8, 2005, at 3:43 AM, Snail Scott wrote:

> At 08:56 PM 5/7/2005 -0500, you wrote:
>> Ron Roy just gave another warning on manganese--I've seen several
>> lately,
>> but a number of my books have slip and glaze recipes with that
>> ingredient.
>> I've used it to create a nice, dark slip for my marbleware, mixed
>> into a red
>> earthenware slip--you've got my attention, what can I use instead?
>
>
> I wouldn't worry excessively. The biggest hazard is
> from fumes during firing, so if you don't have your
> kiln in your workspace, and you don't hang around it
> while you fire (or afterward), the risk should be
> mininal.
>
> If you do share space with your kiln, or you want
> to ditch the manganese anyway, a dark stain may be
> your best choice.
>
> -Snail
>
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Ron Roy on wed 11 may 05


Hi Marcia,

If I had to choose between the two - and I have been thinking about this
for two days now - I still can't make up my mind.

Too much of either is unacceptable.

Chrome fumes and so does manganese.

Chronic systemic exposure to too much chrome can cause asthma and lung
cancer - chromates are potent animal carcinogens.

If you are firing glazes with chrome in them it would be best to have you
kiln room properly ventilated.

Thanks for adding that in Marcia - why so many are opposed to even talking
about this stuff is a mystery to me.

To those who are freaking out with all this talk about some of the dangers
with the materials we use -

We have been ignorant about this stuff for too long and we need to catch
up. Pottery takes a long time to learn - we need to last a long time - be
in shape to do it - because some of our best work will be done at the end
of our lives.

RR

>I know manganese is hazardous but what about chrome. I always thought
>chrome was worse. It was the one first to be banned from our campus
>studio by the hazmat folks.
>marcia

Ron Roy
RR#4
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Brighton, Ontario
Canada
K0K 1H0
Phone: 613-475-9544
Fax: 613-475-3513