Jim Cullen on wed 20 sep 00
Is the bone ash we use in our garden the same quality(?) as the bone ash =
I would use in a glaze?
Just curious.
KEEP CENTERED
Cullen
Naperville, Illinois
Frank Gaydos on wed 20 sep 00
Jim,
Why don't you try a 100 gram batch and let us know.?
Frank Gaydos
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Subject: Bone Ash for the Garden???
Is the bone ash we use in our garden the same quality(?) as the bone ash I
would use in a glaze?
Just curious.
Cullen
Naperville, Illinois
Martin Howard on thu 21 sep 00
The pet crematorium, where I get my pet ash for glazing, sells the rest of
it to gardeners around him. So, in that case it is the same as Bone Meal for
gardeners.
However, I suspect that the normal gardener's bonemeal, the kind you buy in
the garden centre, comes from abattoirs and therefore from the larger
animals, but it must basically be the same.
Why not have some analysed.
My analysis for Pet Ash, carried out by CERAM at Stoke on Trent, was:-
Silica SiO2 1
Titania TiO2 .15
Alumina Al2O3 .6
Ferric Oxide Fe2O3 1
Lime CaO 45
Magnesia MgO 1.4
Potash K2O 11
Soda Na2O 4.5
Chromium Sesquioxide Cr2O3 .02
Cupric Oxide CuO .03
Manganic Oxide Mn3O4 .06
Phosphorus Pentoxide P2O5 28
Sulphur Trioxide SO3 .3
Zinc Oxide ZnO .25
Zirconia ZrO2 .2
LOI 6.66
Total 100
It does make glazes opaque, even over red earthenware.
Martin Howard
Webb's Cottage Pottery
Woolpits Road, Great Saling
BRAINTREE, Essex CM7 5DZ
England
martin@webbscottage.co.uk
Dewitt on thu 21 sep 00
Martin,
I'm curious about the percentages of phosphorus pentoxide (P2O5)
and sulphur trioxide (SO3) in the analysis. If I remember correctly, both
P2O5 and S03 are gasous and very reactive. SO3 and water forms sulfuric
acid and (here again, if I remember correctly) P2O5 and water forms
phosphoric acid. I could understand the trace amount of SO3 in the
analysis, but 28% P2O5 puzzles me and the analysis does need 28% (rather
than .28%) to add up to 100%.
deg (who once nearly poisoned his high school chem class with P2O5)
At 07:38 9/21/00 +0100, you wrote:
>The pet crematorium, where I get my pet ash for glazing, sells the rest of
>it to gardeners around him. So, in that case it is the same as Bone Meal for
>gardeners.
>
>However, I suspect that the normal gardener's bonemeal, the kind you buy in
>the garden centre, comes from abattoirs and therefore from the larger
>animals, but it must basically be the same.
>
>Why not have some analysed.
>
>My analysis for Pet Ash, carried out by CERAM at Stoke on Trent, was:-
>Silica SiO2 1
>Titania TiO2 .15
>Alumina Al2O3 .6
>Ferric Oxide Fe2O3 1
>Lime CaO 45
>Magnesia MgO 1.4
>Potash K2O 11
>Soda Na2O 4.5
>Chromium Sesquioxide Cr2O3 .02
>Cupric Oxide CuO .03
>Manganic Oxide Mn3O4 .06
>Phosphorus Pentoxide P2O5 28
>Sulphur Trioxide SO3 .3
>Zinc Oxide ZnO .25
>Zirconia ZrO2 .2
>LOI 6.66
>Total 100
>
>It does make glazes opaque, even over red earthenware.
>
>Martin Howard
>Webb's Cottage Pottery
>Woolpits Road, Great Saling
>BRAINTREE, Essex CM7 5DZ
>England
>martin@webbscottage.co.uk
>
>______________________________________________________________________________
>Send postings to clayart@lsv.ceramics.org
>
>You may look at the archives for the list or change your subscription
>settings from http://www.ceramics.org/clayart/
>
>Moderator of the list is Mel Jacobson who may be reached at
>melpots@pclink.com.
Dave Finkelnburg on thu 21 sep 00
Dewitt,
The listing of phosphorous in the bone analysis as P2O5 is by
convention, that is, it's the way chemists list things. The phosphorous in
the bone is actually there as a calcium phosphate. Therefore, it's not
reactive at all until you fire it in the glaze or dissolve it with some
acid.
If you compare the number of moles of calcium and phosphorous in the
analysis, I suspect they'll come close to being present in the same ratio as
calcium phosphate, allowing for analytical error and the fact that some
small amount of the calcium is also tied up by other materials than
phosphate.
The SO3 is also listed by convention. The sulfur in the bone ash is
probably present as a sulfate, and will only become SO3 when you roast the
bone ash in the process of firing the glaze.
I hope this helps.
Dave Finkelnburg
-----Original Message-----
From: Dewitt
To: CLAYART@LSV.CERAMICS.ORG
Date: Thursday, September 21, 2000 1:29 PM
Subject: Re: Bone Ash for the Garden???
>Martin,
>
>I'm curious about the percentages of phosphorus pentoxide (P2O5)
>and sulphur trioxide (SO3) in the analysis. If I remember correctly, both
>P2O5 and S03 are gasous and very reactive. SO3 and water forms sulfuric
>acid and (here again, if I remember correctly) P2O5 and water forms
>phosphoric acid. I could understand the trace amount of SO3 in the
>analysis, but 28% P2O5 puzzles me and the analysis does need 28% (rather
>than .28%) to add up to 100%.
>
>deg (who once nearly poisoned his high school chem class with P2O5)
>
>At 07:38 9/21/00 +0100, you wrote:
>>The pet crematorium, where I get my pet ash for glazing, sells the rest of
>>it to gardeners around him. So, in that case it is the same as Bone Meal
for
>>gardeners.
>>
>>However, I suspect that the normal gardener's bonemeal, the kind you buy
in
>>the garden centre, comes from abattoirs and therefore from the larger
>>animals, but it must basically be the same.
>>
>>Why not have some analysed.
>>
>>My analysis for Pet Ash, carried out by CERAM at Stoke on Trent, was:-
>>Silica SiO2 1
>>Titania TiO2 .15
>>Alumina Al2O3 .6
>>Ferric Oxide Fe2O3 1
>>Lime CaO 45
>>Magnesia MgO 1.4
>>Potash K2O 11
>>Soda Na2O 4.5
>>Chromium Sesquioxide Cr2O3 .02
>>Cupric Oxide CuO .03
>>Manganic Oxide Mn3O4 .06
>>Phosphorus Pentoxide P2O5 28
>>Sulphur Trioxide SO3 .3
>>Zinc Oxide ZnO .25
>>Zirconia ZrO2 .2
>>LOI 6.66
>>Total 100
>>
>>It does make glazes opaque, even over red earthenware.
>>
>>Martin Howard
>>Webb's Cottage Pottery
>>Woolpits Road, Great Saling
>>BRAINTREE, Essex CM7 5DZ
>>England
>>martin@webbscottage.co.uk
>>
>>__________________________________________________________________________
____
>>Send postings to clayart@lsv.ceramics.org
>>
>>You may look at the archives for the list or change your subscription
>>settings from http://www.ceramics.org/clayart/
>>
>>Moderator of the list is Mel Jacobson who may be reached at
>>melpots@pclink.com.
>
>___________________________________________________________________________
___
>Send postings to clayart@lsv.ceramics.org
>
>You may look at the archives for the list or change your subscription
>settings from http://www.ceramics.org/clayart/
>
>Moderator of the list is Mel Jacobson who may be reached at
melpots@pclink.com.
>
Martin Howard on fri 22 sep 00
Dewitt has a point when he writes:-
P2O5 and water forms phosphoric acid.>
When I have kiln full of ware with glaze which includes about 10% Pet Ash, I
do need to open the windows and the main doors for a while.
In further experiments I will use that information about SO3 and P2O5 and
try to see what happens. Is the sulphuric acid going off totally as gas, or
is it hanging around in the kiln? Do others have views on this?
Martin Howard
Webb's Cottage Pottery
Woolpits Road, Great Saling
BRAINTREE, Essex CM7 5DZ
England
martin@webbscottage.co.uk
James Cullen on sat 23 sep 00
It's been great(?) watching a simple question of "Bone Ash for the Garden" go full circle. We've covered everything from the chemical makeup to the health hazards to Mad Cow Disease.
Probably the only concrete answer was...mix up a batch and tell us your resullts.(author forgotten, but thanks anyway).
I think that's what I'll have to do.
(All of us are smarter than any one of us, it just takes a longer route to get the message)
KEEP CENTERED
Cullen
Naperville, Illinois
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