Autumn Downey on wed 10 apr 96
Oops. Sorry, sent my looking for a kiln message twice, thinking it had been
returned. But it did arrive and I must have been seeing the routing slip.
It's all quite amazing.
Maybe this topic had already been covered, but I've often wondered about
glazes with high lithium carb content. How good are they for
functionalware? It seems as though alot of molecule space would be
non-silica. Also, how does one manage the grainy consistency that comes
with lithium? (Or maybe using it in any quantity isn't practical for
expense reasons.)???
Thanks.
Autumn Downey
downeya@internorth.com
Yellowknife, NWT, Canada
Michael Banks on sun 11 apr 99
Yep, I'm still awake Craig and I think your theory has some credence. I've
always found lithium a bit of a conundrum and it does seem to exhibit a
dualistic nature. Perhaps it should have been named after the two-faced
Roman god Janus.
A few years ago I test fired a new spodumene sample on its own on a test
tile to 1260 C. The resultant clear glaze crazed conspicuously even though
on compositional grounds it should had a low enough COE to fit the tile
body. The best explanation of this result I felt at the time, was that the
very high Li molar proportion (0.9) in the flux unity formula resulted in a
very low tensile strength glaze. This had the effect of warning me off high
Li glazes. It was also instructive in alerting me to the importance of
strength modifying ions on promoting or suppressing crazing, irrespective of
calculated COE's.
Interestingly in nature, pure lithium aluminosilicate minerals (petalite,
spodumene etc.) only occur in rocks which result from the crystallization of
residual melts. These rocks (pegmatites) only crystallize from
volitile-rich magma left over after vast volumes of solid granite has
already be precipitated out. The liquid residue left over is often very
concentrated in lithium. The lithium remains until the bitter end because
it bonds into aluminosilicate structures with great difficulty. It is
incapable of forming a true feldspar (unlike its sisters Na & K). This is
put down to its small ionic radius for a univalent alkali element, by
geochemists. The reluctance of Li to form bonds with alumina and silica is
suggestive that its bonds in an aluminosilicate glass would be strained and
weak under tension, ie; promote a craze-prone condition. This effect may
only be marked at high concentrations of molar Li. As a low concentration
secondary flux lithium may contribute to a stronger glaze.
This small radius and low charge gives Li ions the ability to diffuse
rapidly in melts as Craig has noted. Conceivably, as a glaze cools from the
surface, lithium could diffuse away from the freezing skin. This would
result in a lithium-rich boundary layer closest to the pot body and a
lithium-deficient upper glaze layer. In the worst case scenario, the
boundary layer could be so enriched in Li that spodumene may crystallize
out. Spodumene inverts at 1082 C and expands by 30% on cooling! The glaze
might craze initially, but then whammo! - at 1082 the lower portion
violently expands. Instant shivering. Plausible??
Michael
Michael Banks,
Nelson,
New Zealand
Craig Martell wrote:
>----------------------------Original message----------------------------
>Hi:
>
>At the risk of being redundant, I'd like to offer a theory or two about why
>lithium bearing materials do such odd things with glazes from time to
time....
(Snip) >I think that the problems may result from lithium's high
coefficient of
>diffusion, or it's ability to migrate and penetrate any kind of silicate
>melt. Lithium is the lightest metal oxide, and the ions are pretty small
so
>it can move around pretty easily in certain types of silicate chains.
(Snip)..
Anyone still awake?
>
>regards, Craig Martell in Oregon
>
Tom Buck on mon 12 apr 99
Michael:
If spodumene undergoes a 30% expansion in volume during the
cooling down of a high lithium oxide glaze, then this surely would produce
a drastic, noticeable shivering/shattering effect. Seems likely that
spodumene, LiAl(SiO3)2 when pure, would form a separate phase in a melt at
1200 - 1300 oC. At what point would this Lithium crystalline material
occur? My guess (and its only a guess) that phase separation would happen
when the original recipe contained Li2O at 5 mole per cent or higher.
I looked at three C10 "flameware" glazes (two cited by Ron Propst)
and he stated they yielded very low expansion glaze suitable for flameware
with equally low expansion (perhaps 2 x 10-6). The Li2O moles were 0.11
and 0.13 or 3.6 - 3.8 mol% (Propst's two recipes were low in silica). A
third low-expansion recipe, cited by Lawrence, showed Li2O at 0.28 but
because of very high alumiona and silica, the mol% of Li2O becomes 2.8%.
So I conclude that somewhere between 4 and 5 mol% Li2O, the
typical highfire glaze likely would misbehave.
Could you Michael (and others) check on recipes with high Li2O
content and see what mol% they have?
Til later.
Tom Buck ) tel: 905-389-2339 & snailmail: 373 East 43rd
St. Hamilton ON L8T 3E1 Canada (westend Lake Ontario, province of Ontario,
Canada).
Janet H Walker on mon 12 apr 99
Michael Banks speculated:
...This small radius and low charge gives Li ions the
ability to diffuse rapidly in melts as Craig has noted.
Conceivably, as a glaze cools from the surface, lithium could
diffuse away from the freezing skin. This would result in a
lithium-rich boundary layer closest to the pot body and a
lithium-deficient upper glaze layer. In the worst case scenario,
the boundary layer could be so enriched in Li that spodumene may
crystallize out. Spodumene inverts at 1082 C and expands by 30% on
cooling! The glaze might craze initially, but then whammo! - at
1082 the lower portion violently expands. Instant shivering.
Plausible??
You bet it's plausible! In fact, this description sounds like it
would exactly explain/describe a pot I have. I've been saving it to
take a picture. The glaze is like a shredded skin, just barely
clinging in spots to its crystalline underlayer, which is attached
to the pot. I'd better get the picture taken before a mild spring
breeze blows the rest of the glaze off the pot.
Jan Walker
Cambridge MA USA
John Baymore on mon 12 apr 99
------------------
(snip)
This would result in a lithium-rich boundary layer closest to the pot body
and a
lithium-deficient upper glaze layer. In the worst case scenario, the
boundary layer could be so enriched in Li that spodumene may crystallize
out. Spodumene inverts at 1082 C and expands by 30=25 on cooling=21 The =
glaze
might craze initially, but then whammo=21 - at 1082 the lower portion
violently expands. Instant shivering. Plausible??
(clip)
Michael,
Not only plausable but I would bet that you hit the nail on the head. This
is the best description that I have seen that fits the results I have
witnessed and also fits the science. Great postulation=21=21=21=21=21 =
Thanks.
You can get a similar type of effect of a crazing glaze that ALSO shivers
off the pot by putting lithium into the body and a relatively higher COE
glaze over it. You get micro fracture planes parallel to the clay/glaze
boundary in the boundry zone. Did a little experimenting with this a
while back.
Now we need someone with easy, free access to an electron microscope =3Cg=3E
and a good section of this type of glaze/body situation to confirm the
hypothesis.
Thanks for a great posting.
BEst,
......................john
John Baymore
River Bend Pottery
22 Riverbend Way
Wilton, NH 03086 USA
603-654-2752
JBaymore=40Compuserve.com
Craig Martell on tue 13 apr 99
Hi:
Yes, Michael, I would think that plausible would more than apply to your
post. I really would be at a loss to explain or understand the behavior of
lithium if I didn't think that it had the ability to move around like it
seems to. If lithium ions migrate into clay-glaze boundary layers it would
seem plausible too that it would form spodumene with the alumina and silica,
as you have proposed. My credentials being somewhat at a loss here, that's
about as far as I can go.
I remember in the first glaze composition and calc class that I had after
doing undergrad work we were exploring cone 6 and cone 10 glazes. So, we
fired a lot of individual materials to see what they would do at the given
temps. I put a one half teaspoon size mound of lithium carb into a small
bowl, maybe 2 inches in diameter and 2 inches deep. We fired all the tests
to cone 6 and checked them out after the firing. The lithium carb mound was
gone and it appeared to have penetrated into the clay. Not only in the
bottom of the bowl, but it had climbed up to the top and had also penetrated
through the rim. If the bowl had been thinner, it may well have saturated
the clay. I don't remember seeing any evidence of shivering at the interior
surface of the small bowl. Mobile stuff!!
Thanks for responding to the post and thanks also to Tom, John, Jan, and
David! I probably forgot someone.
regards, Craig Martell in Oregon
Thonas C. Curran on wed 16 jun 99
While looking for my disappearing CM articles, I came upon an old
brochure on Lithium in Ceramics, published by the Lithium Corp. of
America. The lithium people out there might like a few short quotes:
"There are certain basic properties of lithium which are of interest in
ceramics. Since lithium has a very small ionic radius in comparison to
the other alkali metals, it has a higher field strength. Low expansion
coefficients are general imparted to ceramic compositions containing
lithia. Lithium compounds may be very strong fluxes. This is true for
lithium carbonate and lithium fluoride which promote glass formation at
very low temperatures. In contrast, other lithium complunds may be
quite refractory: lithium zirconate and lithium aluminum spinel are
examples."
"There is very little published information on the use of lithia
compounds in structural ceramics...laboratory investigations indicate
that small additions of lithium compounds will react with quartz during
firing and eliminate the alpha-beta quartz transition in the cooling
cycle. [interesting! my comment.] Lithia has a variety to use in
glasses. It imparts low thermal expansion coefficients to glasses and
also promotes devitrifaction in glass systems..."
"Lithium is the lightest of all metals...exhibits in many of its
properties...same characteristics of the more common alkali metals
sodium and potassium...but in many respects is also shows similarities
with the elements of the alkaline earth group..., esp. magnesium. This
'diagonal similarity' is also found between beryllium and aluminum, and
boron and silicon..."
"Lithium carbonate imparts the properties of chemical resistance, low
thermal expansion, high gloss, etc. Its strong fluxing action reduces
firing temperature and time, improves flow and bonding properties, and
permits enameling of thinner sheet metal..."
address on brochure: Lithium Corporation of America
PO Box 8, Bessemer City, NC 28016
More food for thought? Carolyn
John Britt on mon 1 nov 99
I think what is meant by this is that if you add 1% lithium this
increases the melting. This then allows you to add more alumina and
silica - thus making a stronger glaze.
I'm not saying I agree or disagree, but I think that is the part they
left out.
Date: Sun, 31 Oct 1999 23:28:59 EST
From: "Louis H.. Katz"
Subject: Re: Lithium glazes --
----------------------------Original message----------------------------
There is a bit of bad logic in the assertion that if litium is sometimes
added to increase durability then it must not leach from glazes.
Louis
>
> Second, if you check _Ceramic_Glazes_, 3rd edition, by
> Parmelee and Harman, what you will find is that addition
> of lithium to a glaze for porcelain INCREASES both the
> hardness of the glaze (that is, its resistance to mechanical
> abrasion) and its resistance to chemical attack. In other words:
> no, lithium does not seem to leach out, and yes, it seems to
> be quite safe for food.
----------------
--
Thanks,
John Britt claydude@unicomp.net
Dys-Functional Pottery
Dallas, Texas
http://www.dysfunctionalpottery.com/claydude
http://www.silverhawk.com/ex99/britt/welcome.html
DONALD G. GOLDSOBEL on wed 8 dec 99
I have a question for shino users. I have several recipes for shino type
glazes that call for lithium carbonate, petalite or spodumene. I have a
goodlyt supply of spodumene and want to know how to substitute it for the
other lithium sources. Any help out there?
TIA
Donald in the wintery San Fernando Valley.
Wendy Moore on thu 9 dec 99
How interesting that your post should come the on day I unload a kiln of test
tiles trying to substitute Spod. and Lith. Carb for Petalite in a glaze
called Reitz Green. (We ran out of petalite and the studio is not willing at
the moment to replace and I love the glaze!) I have been able to achieve
similar surface texture, but lack the color depth. If I achieve the color
depth , my surface is too dry. Maybe someone will have some hints...?
Wendy Moore >wendym@globalbiz.net
the apron Lady
DONALD G. GOLDSOBEL wrote:
> ----------------------------Original message----------------------------
> I have a question for shino users. I have several recipes for shino type
> glazes that call for lithium carbonate, petalite or spodumene. I have a
> goodlyt supply of spodumene and want to know how to substitute it for the
> other lithium sources. Any help out there?
>
> TIA
>
> Donald in the wintery San Fernando Valley.
Ron Roy on thu 9 dec 99
Hi Donald,
It can be done - best way is to use calculation. The spod brings with it
lots of silica and alumina and the problem may be that there will be little
or no raw clay in the glaze at the end of the process.
Lithium is added to Shino's to try and stop the crazing from all that KNaO.
If that is what you are trying to do it is best to keep the Li2O to 20% of
the total Li2O+K2O+Na2O. Otherwise you are back to higher expansions again.
Would you notice a change in colour if you subbed lithium for some of the
KNaO in a shino glaze - I doubt it but it would be an interesting
experiment.
If you want to do some testing let me know and I will make up some recipes
starting with one or two of yours.
RR
>----------------------------Original message----------------------------
>I have a question for shino users. I have several recipes for shino type
>glazes that call for lithium carbonate, petalite or spodumene. I have a
>goodlyt supply of spodumene and want to know how to substitute it for the
>other lithium sources. Any help out there?
>TIA
>Donald in the wintery San Fernando Valley.
Ron Roy
93 Pegasus Trail
Scarborough
Ontario, Canada
M1G 3N8
Evenings 416-439-2621
Fax 416-438-7849
David Hendley on fri 10 dec 99
Wendy, replace 10 parts pedalite with 6 parts
spodumene and 4 parts flint.
Spodumene is pretty variable, so this might not be
identical, but it should get you close.
I've done this with Reitz Green for 20 years.
Donald, it's a simple matter to replace the pedalite
with spodumene using the ratio above.
The most accurate way to make the substitution is
with glaze calculation, but this simple formula will
probably be close.
Replacing the lithium carbonate with spodumene is
sometimes difficult because the spodumene adds
alumina and silica to the glaze, which can require you
to remove clay to compensate. Low clay recipes don't
have the clay to spare, but most Shinos have plenty
of clay, so it should not be a problem.
A glaze calculation program will let you do this.
(Or post it to Clayart and someone will do it for you!)
--
David Hendley
Maydelle, Texas
hendley@tyler.net
http://www.farmpots.com/
| ----------------------------Original message----------------------------
| How interesting that your post should come the on day I unload a kiln of
test
| tiles trying to substitute Spod. and Lith. Carb for Petalite in a glaze
| called Reitz Green. (We ran out of petalite and the studio is not willing
at
| the moment to replace and I love the glaze!) I have been able to achieve
| similar surface texture, but lack the color depth. If I achieve the color
| depth , my surface is too dry. Maybe someone will have some hints...?
|
| Wendy Moore >wendym@globalbiz.net
| the apron Lady
|
| DONALD G. GOLDSOBEL wrote:
|
| > ----------------------------Original message----------------------------
| > I have a question for shino users. I have several recipes for shino
type
| > glazes that call for lithium carbonate, petalite or spodumene. I have a
| > goodlyt supply of spodumene and want to know how to substitute it for
the
| > other lithium sources. Any help out there?
| >
| > TIA
| >
| > Donald in the wintery San Fernando Valley.
|
David Hewitt on sat 11 dec 99
I had expected to see Edouard Bastrache reply to this as it seems right
up his street. May I, therefore, quote from his book 'Substitutions for
raw Ceramic Materials' where he gives the following substitutions -
among others.
For every 1% Spodumene substitute 0.197 Lithium Carbonate
0.685 Kaolin
0.318 Silica
or
0.197 Lithium Carbonate
0.272 Alumina
0.638 Silica
or
0.807 Petalite
0.097 Lithium Carbonate
0.140 Alumina
For every 1% Petalite substitute 0.608 Spodumene
0.392 Silica
or
0.120 Lithium Carbonate
0.419 Kaolin
0.585 Silica
or
0.120 Lithium Carbonate
0.166 Alumina
0.780 Silica
I hope that these will be of some help
David
In message , DONALD G. GOLDSOBEL writes
>----------------------------Original message----------------------------
>I have a question for shino users. I have several recipes for shino type
>glazes that call for lithium carbonate, petalite or spodumene. I have a
>goodlyt supply of spodumene and want to know how to substitute it for the
>other lithium sources. Any help out there?
>
>TIA
>
>Donald in the wintery San Fernando Valley.
>
--
David Hewitt
David Hewitt Pottery ,
7 Fairfield Road, Caerleon, Newport,
South Wales, NP18 3DQ, UK. Tel:- +44 (0) 1633 420647
FAX:- +44 (0) 870 1617274
Own Web site http://www.dhpot.demon.co.uk
IMC Web site http://digitalfire.com/education/people/hewitt.htm
Donald G. Goldsobel on sun 12 dec 99
Dave,
I printed the formula for \reitz Green below, is this the one you use and
is the conversion from petalite to spodumene correct. TIA
Donald
Nepheline Syenite 70
Petalite 15
OR
Spdumene 9+
Silica 4
Gerstley Borate 2
Whiting 5
OM4 8
Add: Cobalt Carb 1
Rutile 2%
Wendy, replace 10 parts pedalite with 6 parts
>spodumene and 4 parts flint.
>Spodumene is pretty variable, so this might not be
>identical, but it should get you close.
>I've done this with Reitz Green for 20 years.
>
>Donald, it's a simple matter to replace the pedalite
>with spodumene using the ratio above.
>The most accurate way to make the substitution is
>with glaze calculation, but this simple formula will
>probably be close.
>
>Replacing the lithium carbonate with spodumene is
>sometimes difficult because the spodumene adds
>alumina and silica to the glaze, which can require you
>to remove clay to compensate. Low clay recipes don't
>have the clay to spare, but most Shinos have plenty
>of clay, so it should not be a problem.
>A glaze calculation program will let you do this.
>(Or post it to Clayart and someone will do it for you!)
>
>--
>David Hendley
>Maydelle, Texas
>hendley@tyler.net
>http://www.farmpots.com/
>
>
>
>
>| ----------------------------Original message----------------------------
>| How interesting that your post should come the on day I unload a kiln of
>test
>| tiles trying to substitute Spod. and Lith. Carb for Petalite in a glaze
>| called Reitz Green. (We ran out of petalite and the studio is not willing
>at
>| the moment to replace and I love the glaze!) I have been able to achieve
>| similar surface texture, but lack the color depth. If I achieve the color
>| depth , my surface is too dry. Maybe someone will have some hints...?
>|
>| Wendy Moore >wendym@globalbiz.net
>| the apron Lady
>|
>| DONALD G. GOLDSOBEL wrote:
>|
>| > ----------------------------Original message----------------------------
>| > I have a question for shino users. I have several recipes for shino
>type
>| > glazes that call for lithium carbonate, petalite or spodumene. I have a
>| > goodlyt supply of spodumene and want to know how to substitute it for
>the
>| > other lithium sources. Any help out there?
>| >
>| > TIA
>| >
>| > Donald in the wintery San Fernando Valley.
>|
>
Edouard Bastarache on fri 15 dec 00
Hello all,
a friend and pharmacist recently did a search for me
on the subject of lithium intoxication and the use of lithium carbonate
fluxed glazes, and there is no such thing as a lithium intoxication case
from
using this type of wares.
I just finished doing a search in different databases we use in
occupational medicine and there is no such thing as a case of
lithium intoxication among workers and/or potters using lithium carbonate.
As for users of the drug, the toxic and therapeutic blood levels are
very close; any activity leading to loosing much body water may switch a
patient taking lithium carbonate form the therapeutic to the toxic zone,
as in sweating in the melting departments of a steel mills.
Also many anti-inflammatory drugs raise the lithium blood levels of
patients and may cause the intoxication.
I saw one case 2 years ago. Motrin(Advil) is one of the possible offender=
s,
it is important to remember this name because it may be sold without a
prescription.
So, as far as i am concerned, i am much more afraid of these situations
than picking up a few atoms of lithium from a pot covered by a
lithium-containing
glaze; more specially if the amount used is low, the formula is well
balanced and the pots are high-fired.
Later,
Edouard BastaracheM.D. (Occupational & Environmental Medicine)
Irr=E9ductible Qu=E9becois
Sorel-Tracy
Dans / In "La Belle Province"
edouardb@sorel-tracy.qc.ca
http://www.sorel-tracy.qc.ca/~edouardb/
----- Message d'origine -----
De : Diane G. Echlin
=C0 :
Envoy=E9 : 15 d=E9cembre, 2000 07:36
Objet : Re: Lithium questions
will edwards on mon 18 dec 00
Ron Roy said . "As for the toxicity issue - just to piggy back on what Mo=
nona
said.
Toxicity is - or at least should be linked to body weight. What may be no=
n
toxic to an adult may be toxic to a breast feeding baby - or a fetus. How=
much lithium can a one pound fetus absorb before there is an effect?"
Ron that was wrote beautifully and its well worth everyone looking at. It=
has
fully delivered the correlation of materials from incubation period to
delivery through adult-hood.
When we eat meat now days and veggies from the store and especially the
packaged materials that come with so many strange ingredients no one know=
s
what they are getting, are we delivering trace elements to the fetus?
(Remember, this is an example not a veggie or meat thing)
Of course the fetus is taking in these compounds. The zygote is metaboli=
zing
faster than a run away freight train and storing perhaps some of these in=
their chemical make-up. Chromozonal damage and nerve transmission degrada=
tion
and other factors have to be influenced by these toxins and pollutents. M=
onona
and others here that are into toxicology may be better able to answer thi=
s
than I.
Undestand that lead is absorbed and stored faster during growth than when=
the
growth period ends. What does that tell you? (Corect me here)
Are latter adult diseases associated with certain materials? The propensi=
ty of
having a disease starts with accumulation, exposure and ability to rid on=
es
body of materials that we are exposed to. I even wondered if ADHD might e=
ven
be a culprit of some compound? =
This makes me proud to see someone who admitedly has stated they had very=
minimal schooling along the lines of finishing high-school and college. B=
ut at
the same time we have all seen and (I) have proven, (For my own needs) mu=
ch
that is said by Ron and others have beared some real fruit.
It don't take a rocket scientist to teach you that rocket fuel is dangero=
us.
It does take patience and intent to learn how to make the fuel however.
William Edwards
(Alchemy is now the trend I follow) I find more by accident and magic tha=
n I
do on purpose!
____________________________________________________________________
Get free email and a permanent address at http://www.netaddress.com/?N=3D=
1
Smart on tue 19 dec 00
Hi Clayarters, Tx to translate this text in good english :
L'oxyde de lithium est un composant mineur des gla=E7ures c=E9ramiques. =
Il est peu utilis=E9 et lorsque c'est le cas, c'est en tr=E8s petite =
quantit=E9 (souvent entre 0.2 et 1.5 %). Les propri=E9t=E9s des =
gla=E7ures au lithium ne sont pas tr=E8s stables sauf pour les =
gla=E7ures de haute temp=E9rature qui contiennent aussi beaucoup de =
silice (L=E0 je suis d'accord avec Ron Roy).
Le lithium est beaucoup plus utilis=E9 pour la composition des p=E2tes =
c=E9ramiques, dans le carrelage ou dans le sanitaire. Il permet =
d'abaisser la temp=E9rature de cuisson et de faire des =E9conomies =
d'=E9nergie importantes.
Actuellement cet oxyde ne fait l'objet d'aucune r=E9glementation =
concernant les produits c=E9ramiques et verriers en Europe. Il est peu =
utilis=E9, quasiment absent de la plupart des gla=E7ures c=E9ramiques.
La position d'=C9douard Bastarache sur ce sujet est tout =E0 fait =
honn=E8te et louable. Il y a bien d'autres produits plus dangereux dont =
il faut se pr=E9occuper. =20
Amicalement et Cordialement, Smart
Smart.Conseil
Le site Fran=E7ais d=E9di=E9 aux passionn=E9s de c=E9ramique
The French site dedicated to ceramics lovers
smart2000@wanadoo.fr
http://perso.wanadoo.fr/smart2000/
Earl Brunner on tue 19 dec 00
Je pense que cette chose de lithium a =E9t=E9 sortie enfl=E9e de la=20
proportion. Cependant, mettez le lithium de c=F4t=E9 pendant un moment, u=
n=20
potier responsable doit savoir que ses lustres sont bien =E9quilibr=E9s e=
t=20
lixivient resistent. S' ils sont bien =E9quilibr=E9s et lixivient resiste=
nt,=20
alors nous ne devrions pas vraiment devoir nous inqui=E9ter du lithium ou=
=20
de la plupart des autres mat=E9riaux que nous utilisons habituellement.
Smart wrote:
> Hi Clayarters, Tx to translate this text in good english :
>=20
>
http://coyote.accessnv.com/bruec
mailto:bruec@anv.net
Ron Roy on wed 20 dec 00
The case in point was a low fired glaze with 10% lithium - I agree if the
glaze is well balanced and the amounts of lithium are low - trouble is most
glazes we are using are not durable enough to minimize leaching.
One of the problems with getting lithium from carbonate - instead of
spodumene or petalite for instance - the lithium in carbonate is not bound
to start with - and is somewhat soluble. This means it can migrate and can
be consentrated in certain areas.
All this and we also have the effect on fit which can easily result in
shivering when more than small amount of carbonate are used.
I say - better know what you are doing in terms of stable glazes when using
lithium and make sure you have your glaze tested.
RR
>So, as far as i am concerned, i am much more afraid of these situations
>than picking up a few atoms of lithium from a pot covered by a
>lithium-containing
>glaze; more specially if the amount used is low, the formula is well
>balanced and the pots are high-fired.
Ron Roy
93 Pegasus Trail
Scarborough
Ontario, Canada
M1G 3N8
Evenings 416-439-2621
Fax 416-438-7849
Edouard Bastarache on tue 22 apr 03
Lithium in ceramics
There is no described professional intoxication from the use of this =
element.=20
Data on its toxicity to man come from its use as the treatment of choice =
in manic-depressive states, and from suicidal attempts.
Treatment with lithium carbonate may cause the following :
1-Moderate side-effects:=20
-Diarrhea, nausea,=20
-Feeling of thirst,=20
-Vision troubles,=20
-Tremors of the hands.=20
2-More severe side-effects:=20
-Memory disorders, tremors, muscular fasciculations,=20
-Hyperactive tendon reflexes, dysarthria, giddinesses.=20
3-Severe intoxication leads to convulsions and coma which can be =
hyperosmolar.=20
4-Prolonged treatment :
-Interstitial nephritis, incomplete distal tubular acidosis,=20
-Hyperparathyroidism (hypercalcemia),=20
-Disturbances of the glucose metabolism, obesity,=20
-Goiter, hypothyroidism,=20
-Neutrophilia,=20
-Various cutaneous lesions (psoriasis, acne, folliculitis, alopecia, =
etc.)=20
Toxic manifestations may occur when the serum concentration exceeds =
10.4mg/L.=20
A concentration higher than 25mg/L justifies treatment by dialysis.(1)=20
The toxic and therapeutic blood levels are very close, so any activity =
leading to loosing much body water may switch a patient taking lithium =
carbonate form the therapeutic to the toxic zone, as in sweating =
excessively in melting departments of steel mills.=20
Also many anti-inflammatory drugs raise lithium blood levels of patients =
and may cause the intoxication, one major offender being ibuprofen ( =
Motrin, Advil). It is important to remember this name because it may be =
sold without a prescription.=20
Other possible offenders are ketorolac (Toradol), diclofenac (Voltaren), =
indomethacin (Indocid), naproxen (Naprosyn), fenoprofen (Nalfon), =
celexobib (Celebrex), rofecoxib (Vioxx). (2)
There is no such thing as a single case of lithium intoxication =
described in the=20
pertaining literature from the use of it in glaze making or from the use =
of=20
ceramic wares covered by lithium-containing glazes.
The only lithium compound that is reported as a severe hazard is lithium =
hydride (LiH),=20
which is used as a condensing agent in chemical synthesis with acid =
esters and ketones,=20
as a dessicant (a reducing agent), and as a hydrogen source.=20
The hydride is a severe irritant to skin and mucous membranes=20
because it becomes lithium hydroxide when in contact with moisture=20
of these structures.(3)
So, if you do not use the hydride, have a nice day.
References :
1-Toxicologie Industrielle et Intoxications Professionnelles, Lauwerys =
R. last edition.
2-Sylvie Dumaine, pharmacist, Sorel-Tracy, Quebec, Canada (2002)
3-Occupational Medicine, Zenz Carl, last edition.
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
Edouard Bastarache Inc. on thu 27 jan 05
Lilli abd all,
There is no described professional intoxication from the use of this
element.
Data on its toxicity to man come from its use as the treatment of choice
in manic-depressive states, and from suicidal attempts.
Treatment with lithium carbonate may cause the following :
1-Moderate side-effects:
-Diarrhea, nausea,
-Feeling of thirst,
-Vision troubles,
-Tremors of the hands.
2-More severe side-effects:
-Memory disorders, tremors, muscular fasciculations,
-Hyperactive tendon reflexes, dysarthria, giddinesses.
3-Severe intoxication leads to convulsions and coma which can be
hyperosmolar.
4-Prolonged treatment :
-Interstitial nephritis, incomplete distal tubular acidosis,
-Hyperparathyroidism (hypercalcemia),
-Disturbances of the glucose metabolism, obesity,
-Goiter, hypothyroidism,
-Neutrophilia,
-Various cutaneous lesions (psoriasis, acne, folliculitis, alopecia, etc.)
Toxic manifestations may occur when the serum concentration exceeds
10.4mg/L.
A concentration higher than 25mg/L justifies treatment by dialysis.(1)
The toxic and therapeutic blood levels are very close, so any activity
leading to loosing much body water may switch a patient taking lithium
carbonate form the therapeutic to the toxic zone, as in sweating excessively
in melting departments of steel mills.
Also many anti-inflammatory drugs raise lithium blood levels of patients and
may cause the intoxication, one major offender being ibuprofen ( Motrin,
Advil). It is important to remember this name because it may be sold without
a prescription.
Other possible offenders are ketorolac (Toradol), diclofenac (Voltaren),
indomethacin (Indocid), naproxen (Naprosyn), fenoprofen (Nalfon), celexobib
(Celebrex), rofecoxib (Vioxx). (2)
There is no such thing as a single case of lithium intoxication described in
the
pertaining literature from the use of it in glaze making or from the use of
ceramic wares covered by lithium-containing glazes.
The only lithium compound that is reported as a severe hazard is lithium
hydride (LiH),
which is used as a condensing agent in chemical synthesis with acid esters
and ketones,
as a dessicant (a reducing agent), and as a hydrogen source.
The hydride is a severe irritant to skin and mucous membranes
because it becomes lithium hydroxide when in contact with moisture
of these structures.(3)
So, if you do not use the hydride, have a nice day.
Later,
"Ils sont fous ces Quebecois"
Edouard Bastarache
Irreductible Quebecois
Indomitable Quebeker
Sorel-Tracy
Quebec
edouardb@sorel-tracy.qc.ca
www.sorel-tracy.qc.ca/~edouardb/Welcome.html
http://perso.wanadoo.fr/smart2000/index.htm
http://www.digitalfire.com/education/toxicity/
Edouard Bastarache Inc. on sun 6 jan 08
Hello all,
Richard Zakin, in his programme "Describ9",
says one may use up to 5% Lithium Carbonate
and up to 35% Spodumene in glazes.
Gis la revido,
(A la revoyure)
Edouard Bastarache=20
Spertesperantisto
Sorel-Tracy
Quebec
http://www.flickr.com/photos/30058682@N00/
http://www.flickr.com/photos/potier/20321056/
http://perso.orange.fr/smart2000/livres.htm
http://www.pshcanada.com/Toxicology.htm
http://myblogsmesblogs.blogspot.com/
Steve Slatin on sun 6 jan 08
Edouard --
I don't generally go very high in
lithium, but I do use several lithium
glazes. I find them to be somewhat
unpredictable -- stable on one clay
and unstable on another.
I generally find spodumene sourced
lithium less of a problem than
lithium carb. I have
no idea if that is because of the
chemistry of spodumene at ^6, or
something else (like the underlying
clay).
Of course for vitrifying a recalcitrant
glaze, very small amounts of lithium
carb (like 1% by weight) is wonderful.
-- Steve Slatin
"Edouard Bastarache Inc." wrote:
Hello all,
Richard Zakin, in his programme "Describ9",
says one may use up to 5% Lithium Carbonate
and up to 35% Spodumene in glazes.
Gis la revido,
(A la revoyure)
Edouard Bastarache
Spertesperantisto
---------------------------------
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Hank Murrow on mon 7 jan 08
On Jan 6, 2008, at 10:50 PM, Steve Slatin wrote:
> Edouard --
>
> I don't generally go very high in
> lithium, but I do use several lithium
> glazes. I find them to be somewhat
> unpredictable -- stable on one clay
> and unstable on another.
Dear Steve;
It may be the solubility of Lithium carbonate that is causing the
'reliability' problem.
Cheers, Hank
www.murrow.biz/hank
Steve Slatin on mon 7 jan 08
Hank --
You may well be right. To do a proper test,
I need to make up a set of two test bowl in
every different clay I use (two porcelains,
two white stonewares, one tan, one buff,
one speckled dark, one black) and glaze
them all out of the same bucket at the
same time, using a large enough sample
that the solubility issue will be attenuated
if not eliminated, and then do each of the
two bowls differently -- one a thick
application and the other thin.
Then I'd have to test every dang bowl
for leaching.
I'd have to be an Alisa Clausen to test
in that organized a fashion, and I'm not.
Of course if I could get my act together
well enough to do it just once, I'd finally
establish whether the change in glaze
comp due to solubles in the mix are
what do it or not. Maybe someday.
Best wishes -- Steve S
Hank Murrow wrote:
On Jan 6, 2008, at 10:50 PM, Steve Slatin wrote:
> Edouard --
>
> I don't generally go very high in
> lithium, but I do use several lithium
> glazes. I find them to be somewhat
> unpredictable -- stable on one clay
> and unstable on another.
Dear Steve;
It may be the solubility of Lithium carbonate that is causing the
'reliability' problem.
Cheers, Hank
www.murrow.biz/hank
---------------------------------
Never miss a thing. Make Yahoo your homepage.
Edouard Bastarache Inc. on mon 7 jan 08
Steve and Hank,
check this out.
You will never know before it goes through the test of firing...
If you can, magnify the picture
http://photos1.blogger.com/blogger/2809/1218/1600/BXId.jpg
Hardwood Ash (washed, 200 mesh-sieved), 36
Custer Spar, 14.5
Ferro frit #3134, 23
Kaolin, 14.5
Lithium Carbonate, 12
Bentonite, 2
Ultrox, 15.5
Black Copper Oxide, 3.5
Gis la revido,
(A la revoyure)
Edouard Bastarache=20
Spertesperantisto
Sorel-Tracy
Quebec
http://www.flickr.com/photos/30058682@N00/
http://www.flickr.com/photos/potier/20321056/
http://perso.orange.fr/smart2000/livres.htm
http://www.pshcanada.com/Toxicology.htm
http://myblogsmesblogs.blogspot.com/
Ron Roy on tue 8 jan 08
Depends on the clay body - if there is iron present that may be the
difference. Ask him how many clays he has tried high lithium carb glazes
on.
Hank is correct - it is the partial solubility of lithium Carb that is the
problem. The problem does not happen with spodumene.
The problem with lithium is unique in that you can have both crazing and
shivering on the same pot. David Hewitt and I did a number of experiments
and measured clays and glazes with my dilatometer. We found nothing unusual
with the clays or the glazes - it was the combination that was the problem.
You can probably find his notes if you google him - his web site is still
archived.
RR
>Hello all,
>
>Richard Zakin, in his programme "Describ9",
>says one may use up to 5% Lithium Carbonate
>and up to 35% Spodumene in glazes.
>
>
>Gis la revido,
>(A la revoyure)
>
>Edouard Bastarache
Ron Roy
RR#4
15084 Little Lake Road
Brighton, Ontario
Canada
K0K 1H0
Edouard Bastarache Inc. on tue 8 jan 08
Here is another one high in lithium carbonate
http://photos1.blogger.com/blogger/2809/1218/1600/BVIIId.jpg
Hardwood Ash (Washed), 35
Custer Spar, 14
Ferro frit #3134, 25
Kaolin, 14
Lithium Carbonate, 12
Bentonite, 2
Ultrox, 15
Cobalt Oxide, 5
Gis la revido,
(A la revoyure)
Edouard Bastarache=20
Spertesperantisto
Sorel-Tracy
Quebec
http://www.flickr.com/photos/30058682@N00/
http://www.flickr.com/photos/potier/20321056/
http://perso.orange.fr/smart2000/livres.htm
http://www.pshcanada.com/Toxicology.htm
http://myblogsmesblogs.blogspot.com/
Ron Roy on thu 10 jan 08
And again - a reminder that using large amounts of Lithium carb can result
in unusual fit problems with glazes over some clays. If you ask me what
amounts of lithium carb would not present problems - I would say 2% at
most.
RR
>Here is another one high in lithium carbonate
>
>http://photos1.blogger.com/blogger/2809/1218/1600/BVIIId.jpg
>
>Hardwood Ash (Washed), 35
>Custer Spar, 14
>Ferro frit #3134, 25
>Kaolin, 14
>Lithium Carbonate, 12
>
>Bentonite, 2
>Ultrox, 15
>Cobalt Oxide, 5
>
>
>
>Gis la revido,
>(A la revoyure)
>
>Edouard Bastarache
Ron Roy
RR#4
15084 Little Lake Road
Brighton, Ontario
Canada
K0K 1H0
Steve Slatin on thu 10 jan 08
Edouard -- It's a beauty. Does it pass the
acid test?
The lithium is about as high as I've ever
seen, the silica is very low, total alkalis
are extremely high, Mg and Ca very
high ... not a predictable result at all!
Was is maybe a rather low firing temp
experiment?
In awe -- Steve Slatin
"Edouard Bastarache Inc." wrote:
Steve and Hank,
check this out.
You will never know before it goes through the test of firing...
If you can, magnify the picture
http://photos1.blogger.com/blogger/2809/1218/1600/BXId.jpg
Steve Slatin --
History teaches us that there have been but few infringements of personal liberty by the state which have not been justified ...
in the name of righteousness and the public good, and few which
have not been directed ... at politically helpless minorities.
-- Harlan Fiske Stone
---------------------------------
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Edouard Bastarache Inc. on thu 10 jan 08
Ooops, I just got it the usual way
----- Original Message -----
From: "Steve Slatin"
To:
Sent: Thursday, January 10, 2008 7:02 PM
Subject: Re: Lithium
> Edouard -- It's a beauty. Does it pass the
> acid test?
>
> The lithium is about as high as I've ever
> seen, the silica is very low, total alkalis
> are extremely high, Mg and Ca very
> high ... not a predictable result at all!
>
> Was is maybe a rather low firing temp
> experiment?
>
> In awe -- Steve Slatin
>
>
> "Edouard Bastarache Inc."
> wrote:
> Steve and Hank,
>
> check this out.
>
> You will never know before it goes through the
> test of firing...
>
> If you can, magnify the picture
>
>
> http://photos1.blogger.com/blogger/2809/1218/1600/BXId.jpg
>
> Steve Slatin --
>
> History teaches us that there have been but few
> infringements of personal liberty by the state
> which have not been justified ...
> in the name of righteousness and the public
> good, and few which
> have not been directed ... at politically
> helpless minorities.
> -- Harlan Fiske Stone
>
> ---------------------------------
> Looking for last minute shopping deals? Find
> them fast with Yahoo! Search.
>
> ______________________________________________________________________________
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