Ron Roy on fri 10 may 02
Hi June - yes Insight was shipped for many years with a theoretical
analysis - I did my best but until recently that is the way is was.
This gives some idea of how far wrong you can get by using theoretical
analysis - one aspect is the LOI - over 20% in all the following % analysis
Here are the analysis I have - take your pick - I do not have an analysis
for the current supply - I suggest you contact Laguna for it - better still
have them post it to ClayArt.
Hope this clears up the misunderstanding - Best regards - RR
Gers Borate - from Hammill and Gillespi.
Entered into Insight june 92. Lot # 5930 << replaced by 9/97 analysis
B2O3 - 28.3
Na2O - 4.7
SiO2 - 9.8
Fe2O3 - 0.35
Al2O3 - 1.3
MgO - 3.5
CaO - 17.9
K2O - 0.14
H2O - 0.52
LOI - 29.1 (Last two added together for LOI of 29.62)
Total - 95.61
From H&G - recieved May 94 & Aug 97(they don't give lot #'s anymore)
B2O3 - 27.68
Na2O - 4.29
SiO2 - 11.73
Fe2O3 - 0.48
Al2O3 - 1.63
MgO - 4.19
CaO - 19.06
K2O - 0.38
H2O - 5.71
LOI - 23.64 (Last two added together for LOI of 5.71+23.64=29.35 )
Total - 98.79
From H&G received Aug 97. Note - identical to above.<<<< I'm using this one
now
B2O3 - 27.68
Na2O - 4.29
SiO2 - 11.73
Fe2O3 - 0.48
Al2O3 - 1.63
MgO - 4.19
CaO - 19.06
K2O - 1.38
H2O - 5.71
LOI - 23.64 (Last two added together for LOI of 5.71+23.64=29.35)
Total - 98.79
From H&G May/99 (Na20,K2O and MgOdown, Silica and Alumina well up)
B2O3 - 25.7
Na2O - 2.9
SiO2 - 21.2
Fe2O3 - trace
Al2O3 - 7.0
MgO - trace
CaO - 18.9
K2O - trace
LOI - 22.5
Total - 98.2
>Ron, I ran frit 3124 through Tony Hansen's program.Insight and matched it
>(very closely) empirically with the formula I posted. I just re-checked it
>and on the Tony Hansen software, the recipes side to side, are empirically
>very, very close.
>Now either one of us is not understanding something or the program is doing
>something screwy.
>The formula I posted was not a substitute for her glaze recipe. It is only
a
>recipe to make up a batch of material to mix as substitute for Frit3124.
>When I rechecked them side by side, both 100 of my frit 3123 sub and 100
of
>frit 3124 show.55 moles of B2O3, .7 Cao, etc.
>Tony's Gerstley borate formula does not show any mgo, which is why none is
in
>my substitute.
>Gerstley Borate is more often shown as this which I just found, using a web
>search
>2Cao . 3B2O3 . 5H2O
>
>This is the same formula that Rhodes gives in Clay and glazes. Parmalee, as
>far as I could find in a quick search, only addresses Colemanite (same
>formula as shown above for the gerstley).
>I see that Tony on his web site of gerstley subs, lists gerstley borate
>rationalized, which does include Mgo, but it is not in the formula in his
>software, nor in the source for the one I listed above. I don't know what
it
>means by rationalized. I know that gerstley has been somewhat inconsistent
in
>it's formula over the years, so I'm assuming that at one time it had, or
now
>has MgO in it????
>I'll have to check with a current source to see what formula they're using
>since I have two new bags of it.
Ron Roy
RR #4
15084 Little Lake Road
Brighton
Ontario
Canada - K0K 1H0
Phone: 613-475-9544
Fax: 613-475-3513
Timothy Sullivan on fri 10 may 02
Ron - Below is the response that I just got from Laguna when I asked for a
current analysis of GB. It seems somewhat less than entirely useful.
Based on all the info I've seen, GB became less attractive over time due to
a
continual dropping of the percentage of B2O3, and thus the decision was made
to stop mining. Given this, and the fact that our supplier has not had a
working analysis since 1996, it seems that using the GB that is available
today is more of a crap shoot than most other materials. I'm at a loss as
to
what analysis makes the most sense, but even 28% B2O3 seems questionable let
alone everything else.
If I have any of this wrong or you have any additional info I would love to
hear it.
Thanks
Tim Sullivan
Creekside Pottery - Marietta, GA
From Laguna
Subject: RE: Technical Question
Hi Tim------there is no "current" analysis available. The last time we
received an analysis from the mine was in 1996 and it is as follows:
B2O3 28%
Na2O 5.3
CaO 20.6
Water of crystallization 25.0
free water .03
water insoluble,
(inert shales) 18.7
The mine is no longer in the Gerstley Borate business and no new analysis
will be forth coming.
Jon Pacini
Clay Manager
Laguna Clay Co
Ron Roy on fri 17 may 02
Hi Tim,
Your are right - what is provided here is useless - you need the complete
analysis to be able to adjust by calculation.
I would think Laguna should bear the expence of providing a real analysis
seeing as they are the ones selling this. Seems only right to give potters
a chance to make the adjustments necessary to use the latest GB.
My feeling is - go to a Frit (3134) and maybe some CadyCal if you can't get
enough B203 with just the Frit.
RR
>Ron - Below is the response that I just got from Laguna when I asked for a
>current analysis of GB. It seems somewhat less than entirely useful.
>
>Based on all the info I've seen, GB became less attractive over time due to
a
>continual dropping of the percentage of B2O3, and thus the decision was
made
>to stop mining. Given this, and the fact that our supplier has not had a
>working analysis since 1996, it seems that using the GB that is available
>today is more of a crap shoot than most other materials. I'm at a loss as
to
>what analysis makes the most sense, but even 28% B2O3 seems questionable
let
>alone everything else.
>
>If I have any of this wrong or you have any additional info I would love to
>hear it.
>
>Thanks
>Tim Sullivan
>Creekside Pottery - Marietta, GA
>
>From Laguna
>Subject: RE: Technical Question
>
>Hi Tim------there is no "current" analysis available. The last time we
>received an analysis from the mine was in 1996 and it is as follows:
>B2O3 28%
>Na2O 5.3
>CaO 20.6
>Water of crystallization 25.0
>free water .03
>water insoluble,
>(inert shales) 18.7
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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