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mercury in clay

updated sat 30 nov 96

 

Jamie Harvie on tue 19 nov 96

HI,
I am a engineer currently employed to work on reducing the wastewater
discharge of mercury and lead from various sources within our community. As
a potter, I was curious to see what our local Art Instiute was contributing.
Based on wastewater sampling the concentration of mercury in the wastewater
is as high as many local industries. By backtracking and testing frequently
used glazes ingredients I found the highest source of mercury in Ball Clay
and Albany Slip. Three sources of Ball clay tested have a concentration of
about 170 ppb. Another source of Ball clay is at 258.While this is not a
short term health concern it is a long term concern for ecosystem health.
Does anyone have any other information on this subject (mercury in ball
clay)? What are the domestic sources of ball clay? What I would like to do
is sample/find the lowest mercury concentration ball clay and recommend it
for use. Do ball clay suppliers give this information? If anyone can help me
out please, e-mail or give me a call. Thanks Jamie H.

jharvie@wlssd.duluth.mn.us
218-722-3336

Tony Hansen on wed 20 nov 96

>I found the highest source of mercury in Ball Clay and Albany Slip.
>Do ball clay suppliers give this information?

Wow. I work for Plainsman Clays and we and our parent company mine
hundreds of thousands of tons of ball and stoneware clays. We've had
them analysed lots of times and I never saw any mercury on the lab
reports. I'd be happy to send samples for testing.

Check the website at http://www.ceramics.com
Lots of the clay suppliers have pages there.

--
Tony Hansen, IMC - Pulishers of INSIGHT, FORESIGHT, Magic of Fire
web: http://digitalfire.com/imc.html

David G Brown on wed 20 nov 96

Hi Jamie,

If you find it hard to get the info from suppliers you might start your own
testing from samples sent to you by Clayarters. Hope you folks don't mind
my volunteering you.

I would definitely like to buy less harmful ingredients in general. Good luck!

David in Redwood City,CA

JJHerb@aol.com on thu 21 nov 96

170 parts per billion - you could have said 170,000 parts per trillion. It
sounds lots bigger. And much worse. For the dis-en-calculatored among us, I
estimate this is a ball of liquid mercury about 2.5 millimeters in diameter
(look at a ruler) dispersed in a ton - that is 40 boxes that contain 2
twenty-five pound bags each. (.2 gram per ton) Let s see, where shall I
place this on my list of hazards. Below driving a car, below playing paint
ball, . There it is! It goes between getting hit in the head by a meteorite
on a Tuesday and getting hit by a comet at all. I m glad I got that cleared
up, I can go back to worrying about being abducted by space aliens. 170 ppb
- Geez. I am just guessing but it is possible that this amount of mercury
occurs in 2 gallons of interior latex wall paint. That's a better thing to
worry about.

Joseph Herbert
JJHerb@aol.com

Kirk Morrison on fri 22 nov 96

On 21 Nov 96 at 17:29, JJHerb@aol.com wrote:

> ----------------------------Original message----------------------------
> 170 parts per billion - you could have said 170,000 parts per trillion. It
> sounds lots bigger. And much worse. For the dis-en-calculatored among us, I
> estimate this is a ball of liquid mercury about 2.5 millimeters in diameter
> (look at a ruler) dispersed in a ton - that is 40 boxes that contain 2
> twenty-five pound bags each. (.2 gram per ton) Let s see, where shall I
> place this on my list of hazards. Below driving a car, below playing paint
> ball, . There it is! It goes between getting hit in the head by a meteorite
> on a Tuesday and getting hit by a comet at all. I m glad I got that cleared
> up, I can go back to worrying about being abducted by space aliens. 170 ppb
> - Geez. I am just guessing but it is possible that this amount of mercury
> occurs in 2 gallons of interior latex wall paint. That's a better thing to
> worry about.
>
> Joseph Herbert
> JJHerb@aol.com
>
Gee, in my old job at a water plant, before I was injured on duty, I
was exposed to more Mercury and Cyanide everytime I had to handle the
dry chemicals than that amount. Pardon me while I go off on one of my
Hatter binges and stop breathing for a bit. Seriously I do think
your total lack of any concern on the mercury danger is very very close
to right on the money though. After all even radiation in small enough
levels will not effect people over a normal life time. Last time I saw
figures on background radiation from the soil, which clay is, it would
on average take 2400 years to kill you, gamma I think it was, with a
time weighted average of 24 hrs a day 7 days a week, 365 days a year.
If you were only around it 8 hrs a day 5 days a week the risk would go way down
Thanks for pointing out how we can get carried away at times with non
risk, risks.