Bill Edwards on sat 1 nov 03
I have fired with blue marl/clay for testing. Heck, it
might have been some of the clay that Jon Brinley
provided me once upon a time? Lots of folk artist in
Georgia, TN and Al would have had used this as well as
the standard red and sometimes white river clays. The
blue that I personally seen was excavated and found
what looked like between two coal layers or dark
layers of highly compressed clays which was about 15
to 20 down. Pop outs from impurities can be an issue
such as in shell content where calcia and magnesium
are present. Also stay out of the firing zone while
heating up since other obnoxious fumes are generated
from found clays and are of many varieties.
Vince - that sight you gave out would have been a gold
mine for me but that old house I bought has eaten up
almost every penny I had. I wish I could afford to
make an offer on the gas kiln and the extruder. Those
pieces looked in good shape! These kinds of finds are
rare and I appreciated the chance to at least have a
look.
Clays - The same can be said about the analysis of our
coloring oxides as well as for clay. Most should (some
do) readily supply this information especially since
it wouldn't be considered as much a trade secret as
the clays would unless its a blended set of oxides.
Also the bag analysis for raw product should be easily
obtained but sometimes its pretty hard getting facts
and figures in front of you that are accurate and up
to snuff. MSDS are usually generalized and not the
appropiate information here in the USofA for tactical
assault on forming recipes but they do supply handling
information and safety info and shipping data and
weather or not its regulated. The material data
analysis information is something I try to get when I
change or make new adjustments and need to up-date my
files. I spoke on this in depth, here while back on
the oxides and raw chemical accessment information but
felt some might noy be in agreement so I dropped the
subject. I have and always will believe that the only
way to fully get to the bottom of problematic glazes
and possibly clays is to have this information so you
can trace drifts in material when they occur and they
do occur in natural products. Frits and commercially
developed products usually fall within a +/- area that
is really narrow and most likely less problematic when
it comes to calculation based on my personal
experience. A great example of needing an analysis for
chemicals would be gerstley borate that worked good
one batch and worked you to death the next batch. Not
predictable and seldom had any analysis that would
benefit a potter. The flip side is I believe
manufacturers should be able to keep their trade
secrets. I think they could provide a raw analysis
which does not give a tight mix but the information
would give those using calculations a chance to fix
their glazes when problems occur. I sincerely doubt
that anyone would spend what it would take to test a
product and repeat it as far as clay go's and
colorants unless the company its self stopped
production. Gerstley was another issue where some felt
they could mimmick the effect to some degree and
because the product was natural and might be
syntheically formed to fill a void once mining ceased.
If someone removed a very popular porcelain or other
clay that was highly sought after of course some
company would make an attempt to get as close as
possible to a 'HOT' seller due to economics involved.
Gertsley was used widely as a glaze additive/component
whereas many products out there are just now beginning
to see half the use that gertsley seen over the years.
Ball clays and Neph Syen and a few other stand bys
have had a successful run over the years but take one
of them away and you would once again see a swarm of
make-overs to replace them. But un-like gerstley some
could be replicated close enough to work, some might
not? The analysis paints a picture if you do
chemistry, and it sometimes says it will work but upon
actually use we find there is some difference if it
works at all. With good analysis and a good
understanding of heat work we can usually get
semi-reproducible products that work well and look the
same or similar without a lab test from batch to
batch. Testing and tight roping your information and
keeping good records is a major thing in staying on
top of this every changing world.
I lost my number where I called Arti a month of so
back and have no idea if he is still in the hospital
or not? If anyone has any information it would be
great to know how he is doing?
Bill Edwards
=====
http://www.tallapoosariverpottery.com/
Bill Edwards
PO Box 267
Lafayette, AL, 36862
__________________________________
Do you Yahoo!?
Exclusive Video Premiere - Britney Spears
http://launch.yahoo.com/promos/britneyspears/
Jon Brinley on sun 2 nov 03
Bill,
Never had a problem with odor, though it can be an issue. Have fired =
many times with this "found" material and a love, hate relationship has =
developed. maybe it's the glazes...I don't know.
Its always a crap shoot with anything free anyway. I do like the dark =
characteristic's of this clay. It gives my work, the look I want. =
Although the inclusions are a fault to work around. They can be dealt =
with. I am always looking at road widening projects to find more "free" =
clay. As a working stiff/ hobbyist, I need all the free stuff I can get. =
You know insurance and the like .... Oh this issue has been covered.=20
This material does seem to like the other found glaze materials that I =
have recently discovered. Working in an industrial environment has its =
advantages. Lots of goodies to try in the kiln. Many with MSDS, analysis =
and the like. Info to tell if food safe or not , even at high temps. God =
I love my job.=20
Jon in Midland
Where the Sweetgums grow tall
----- Original Message -----=20
From: Bill Edwards=20
To: CLAYART@LSV.CERAMICS.ORG=20
Sent: Saturday, November 01, 2003 2:31 PM
Subject: Blue Marl way down under
I have fired with blue marl/clay for testing. Heck, it
might have been some of the clay that Jon Brinley
provided me once upon a time? Lots of folk artist in
Georgia, TN and Al would have had used this as well as
the standard red and sometimes white river clays. The
blue that I personally seen was excavated and found
what looked like between two coal layers or dark
layers of highly compressed clays which was about 15
to 20 down. Pop outs from impurities can be an issue
such as in shell content where calcia and magnesium
are present. Also stay out of the firing zone while
heating up since other obnoxious fumes are generated
from found clays and are of many varieties.
Vince - that sight you gave out would have been a gold
mine for me but that old house I bought has eaten up
almost every penny I had. I wish I could afford to
make an offer on the gas kiln and the extruder. Those
pieces looked in good shape! These kinds of finds are
rare and I appreciated the chance to at least have a
look.
Clays - The same can be said about the analysis of our
coloring oxides as well as for clay. Most should (some
do) readily supply this information especially since
it wouldn't be considered as much a trade secret as
the clays would unless its a blended set of oxides.
Also the bag analysis for raw product should be easily
obtained but sometimes its pretty hard getting facts
and figures in front of you that are accurate and up
to snuff. MSDS are usually generalized and not the
appropiate information here in the USofA for tactical
assault on forming recipes but they do supply handling
information and safety info and shipping data and
weather or not its regulated. The material data
analysis information is something I try to get when I
change or make new adjustments and need to up-date my
files. I spoke on this in depth, here while back on
the oxides and raw chemical accessment information but
felt some might noy be in agreement so I dropped the
subject. I have and always will believe that the only
way to fully get to the bottom of problematic glazes
and possibly clays is to have this information so you
can trace drifts in material when they occur and they
do occur in natural products. Frits and commercially
developed products usually fall within a +/- area that
is really narrow and most likely less problematic when
it comes to calculation based on my personal
experience. A great example of needing an analysis for
chemicals would be gerstley borate that worked good
one batch and worked you to death the next batch. Not
predictable and seldom had any analysis that would
benefit a potter. The flip side is I believe
manufacturers should be able to keep their trade
secrets. I think they could provide a raw analysis
which does not give a tight mix but the information
would give those using calculations a chance to fix
their glazes when problems occur. I sincerely doubt
that anyone would spend what it would take to test a
product and repeat it as far as clay go's and
colorants unless the company its self stopped
production. Gerstley was another issue where some felt
they could mimmick the effect to some degree and
because the product was natural and might be
syntheically formed to fill a void once mining ceased.
If someone removed a very popular porcelain or other
clay that was highly sought after of course some
company would make an attempt to get as close as
possible to a 'HOT' seller due to economics involved.
Gertsley was used widely as a glaze additive/component
whereas many products out there are just now beginning
to see half the use that gertsley seen over the years.
Ball clays and Neph Syen and a few other stand bys
have had a successful run over the years but take one
of them away and you would once again see a swarm of
make-overs to replace them. But un-like gerstley some
could be replicated close enough to work, some might
not? The analysis paints a picture if you do
chemistry, and it sometimes says it will work but upon
actually use we find there is some difference if it
works at all. With good analysis and a good
understanding of heat work we can usually get
semi-reproducible products that work well and look the
same or similar without a lab test from batch to
batch. Testing and tight roping your information and
keeping good records is a major thing in staying on
top of this every changing world.
I lost my number where I called Arti a month of so
back and have no idea if he is still in the hospital
or not? If anyone has any information it would be
great to know how he is doing?
Bill Edwards
=3D=3D=3D=3D=3D
http://www.tallapoosariverpottery.com/
Bill Edwards
PO Box 267
Lafayette, AL, 36862
__________________________________
Do you Yahoo!?
Exclusive Video Premiere - Britney Spears
http://launch.yahoo.com/promos/britneyspears/
=
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Moderator of the list is Mel Jacobson who may be reached at =
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