Stuart Altmann on fri 7 jun 96
John Byrd asked about the composition of diatomaceous earth. This material
is a marine sediment consisting primarily of the skeletons of diatoms,
which are microscopic algae. The skeletons consist almost entirely of
silica, though other material may be present in the sediment.
Very thick deposits of this material are being mined in the vicinity of
Lompoc, California, in Kenya, right off the road between Nairobi and Kisii,
and probably elsewhere in the world where there are uplifted marine
I visited one of the Lompoc mines a number of years ago to obtain hunks of
the unpulverised diatomite, right off the mine face. The mine geologists
were amused when I explained that I wanted it for sculpture, and very
cooperative. (One of them even presented me with a hunk of California
serpentine, which is virtually the same as jade, and one of these days I'll
get around to carving it.) Diatomite is about as hard as soapstone, which
means that you can easily carve it with a pocket knife. It has bands of
sediment, which look like wood grain, but in carving, it seems grainless.
The bands are tan, probably from iron.
Diatomaceous earth, i.e., pulverized diatomite, is used in a wide variety of
industries, e.g. as a mild abrasive, for refining sugar, and as an
insulation in boilers and blast furnaces. (Do any potters use it as a kiln
insulation? Maybe by holding it together with just enough clay to make a
slurry?) It is the main material used to clarify water in swimming pools,
and a swimming pool supply house might be the easiest place to get it. It
should be cheap. The Shedd Aquarium, here in Chicago, uses tons of it to
clarify their water.
Diatomaceous earth is not usually pulverized finely, the way ceramic silica
is. Still, you might get some interesting results. Give it a try and
report back to us.
CaroleER@aol.com on sat 8 jun 96
In a message dated 96-06-07 18:55:13 EDT, you write:
Diatomaceous earth (not the swimming pool grade) also kills fleas, ants,
roaches, mosquitos etc. Put a little in your pet's food and it'll keep them
from getting worms n stuff. Again, this is not swimming pool grade.
>Diatomaceous earth, i.e., pulverized diatomite, is used in a wide variety of
>industries, e.g. as a mild abrasive, for refining sugar, and as an
>insulation in boilers and blast furnaces. (Do any potters use it as a kiln
>insulation? Maybe by holding it together with just enough clay to make a
>slurry?) It is the main material used to clarify water in swimming pools,
>and a swimming pool supply house might be the easiest place to get it. It
>should be cheap. The Shedd Aquarium, here in Chicago, uses tons of it to
>clarify their water.
RedIron Studios on wed 3 feb 99
Someone on the list was asking what diatomaceous earth can be used
for. One use I know is that we had a bad cockroach problem when we
first moved into our new studio place. We brought in a natural pest
management company. This company used diatomaceous earth to rid
our studio of cockroaches. Basically what they do is use a small pressurized
sprayer (dry sprayer - at home you could just use a brush) to spray the
powder into cracks around the plumbing, inside the cracks in cupboards,
along the floorboards etc. Basically any crack a cockroach can squeeze
into they spray distomaceous earth. A cockroach can squeeze into a 10mm
crack (thats very small space - less than the spaces between these words.)
What was the verdict? Amazingly it's so safe you can eat it as far as pest
management goes. in 3 weeks there was not another cockroach to be seen.
How does it work? Well what happens is the little buggers walk through it
and it gets into all thier joints and basically cuts them to pieces. It works I
would have never believed it but it works better than anything I have seen
Craig Martell on thu 4 feb 99
Rediron studios said, about diatomaceous earth and cockroaches:
> How does it work? Well what happens is the little buggers walk >through
it and it gets into all thier joints and basically cuts them to >pieces. It
works I would have never believed it but it works better than >anything I
have seen before
The ones that aren't shredded will probably die of silicosis from breathing
the dust. Diatomaceous earth can be used in ceramics as a form of amorphic
later, Craig Martell in Oregon
: Terraopera on thu 4 feb 99
Diatomaceous earth is used by painters to give texture to the canvas, much the
same as sand or other dirt. Swimming pools use it in filtering systems.
There's two more uses. Kim
John Fazzino on thu 4 feb 99
Is diatomaceous earth the same as Bentonite?
Joseph Herbert on sat 6 feb 99
John Fazzino wrote: Is diatomaceous earth the same as Bentonite?
Diatomaceous earth is composed of the opalescent silica shells of
microscopic free swimming plants while bentonite is a swelling
montmorillinite clay mineral that results from the weathering of
volcanic ash deposits. I guess you would have to say, "No, they are not
Phyllis E. Tilton on sun 7 feb 99
I have a very old textbook written by Heinrich Ries,PH D, Professor of
Economic Geology in Cornell Univ. title: Clays,Their Occurence,Properties, and
Uses With Especial Reference to Those Of the United States. Copyright 1906
and 1908.(I also have a book by C.F.Binns,The Potter's Craft, copyright 1910.)
In the Ries book, the clays have been researched as to when the deposits
formed historically. He lists such times as Triassic, Paleozoic,
He lists diatomaceous earth in the Tertiary and Pleistocene formations of the
coastal-plain area in Virginia. " The diamotaceous earths form an extended
series of deposits along the Rappahannock River and around Richmond, but they
are worked at one locality, namely Wilmont, to make boiler-seting brick and
fireproofing." The book does not show California having this but it makes
sense that it would be there because of the microscopic shells.
In another book,The Dispensatory of the United States of America,24th
(The first edition was 1833). It is a pharmaceutical tome and at one time an
essential resource in a pharmacy. It lists the chemical formulas of both
bentonite and kaolin-they are amazingly similar. They are both described as
being native,colloidal, hydrated aluminum silicate. An 'over the counter'
product,Kaopectate, used for gastro-intestinal problems, has kaolin as an
ingredient to coat the lining of an irritated gut since it is insoluble.
Kaolin and bentonite are used in many ways, the bentonite in dermatological
products, 2th pastes,etc,etc.
There now, I have told you more than you really wanted to know, hope it isn't
too long. Now I have a question. What is a French butter dish?
terryh on mon 8 feb 99
i have no idea why "diatomite" is being discussed in clayart. here is my
"trivia" infomation about diatomite in CA: diatomite is abundant in
california. belridge oil field produces oil not only from shallower tulare
formation but also from deeper diatomite formation. diatomite is fossil and
shows very interesting petrophysical properties. very high porosity up tp 60 %
yet very low permeability (fluid conductivity). potentially lots of oil but
very hard to retrieve!
Stephani Stephenson on wed 12 apr 00
Just curious. Does anyone use diatomaceous earth in their ceramics
process or as a glaze ingredient in any way?
Gene and Dolita Dohrman on tue 20 jan 04
Not that I want to be accused of being an alarmist, but...
I used to have about 6 salt-water aquariums and diatomaceous earth was a
highly effective filtering agent when used properly. However, if I remember
correctly, it is considered deadly when inhaled so please be careful when
using it. I think I would go with the little pots of beer level with the
ground. You can also sprinkle salt on the little buggers but it must be a
horrible way to die. Drowning in beer sounds much better!
T. Phillips on tue 20 jan 04
As Dolita correctly points out, diatomaceous earth should not be
inhaled. It's composed primarily of silica. If anyone's interested,
scroll down near the bottom of this web page for a breakdown:
Or here for a discussion of its use in pest control:
would-have-been third generation pet store owner, freezing here in
Al Sather on tue 20 jan 04
I was going to flame you for derogating a favorite pesticide that I
considered safe. But, I looked up the MSDS at the following URL
and found that you are absolutely correct. Now, common sense should prevail
such that one would not want to inhale any strange fine white powder, but
Dogberry Clay Studio
Maple Ridge, British Columbia
From: Clayart [mailto:CLAYART@LSV.CERAMICS.ORG] On Behalf Of Gene and Dolita
Sent: Tuesday, January 20, 2004 11:15 AM
Subject: Re: [CLAYART] diatomaceous earth
<> However, if I remember
correctly, it is considered deadly when inhaled so please be careful when
Send postings to firstname.lastname@example.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