David Finkelnburg on tue 11 may 10
Flint is a common, naturally occurring form of silica found as nodules
and seams in limestone in Great Britain and Europe. Unlike quartz, flint
contains significant amounts of impurities including calcium, sometimes
magnesium. I know I'm not the only one to post this. I've read it here
before, too. At one time flint was the purest, most readily available for=
m
of silica available to potters who first brought pottery making to our
shores. Flint is very uncommon in North America. However, the word stuck
and the label flint has now been broadened here in the US and Canada to
embrace a lot of sources of relatively pure silica. Here flint is a synony=
m
for ground quartz.
Lest you think this is all simple, pity the poor geologist who also has t=
o
deal with the question, "What is flint?" For geologists the line between
flint--an impure, dense, hard, opaque silicate mineral classified as a cher=
t
--and chert itself is a subject of ongoing debate. We aren't the only ones
who can be anal about words.
Good potting,
Dave Finkelnburg
http://www.mattanddavesclays.com
Frances Howard on tue 11 may 10
Flint is mostly found in beds of chalk such as the white cliffs of Dover
and lots of other chalk formations especially common to the south of
England. It's a form of limestone but it doesn't look like limestone. (I
don't know about European chalk beds). It always looks odd to find
chunks/nodules of hard yellow flint lying around in the soft chalk but it
all stems from its origin in cretaceous seas. These are the flints used to
make prehistoric tools as they can be chipped and flaked into shape. And =
I
suppose that is the origin of the word too. Nobody talks of silica tools.
And I suppose people would have been used to flint in that area a long time
before they made pottery.
. And since there is no chalk (I think) in north America there can't be
that type of flint here.
Frances Howard
--------------------------------------------------
From: "David Finkelnburg"
Sent: Tuesday, May 11, 2010 1:45 PM
To:
Subject: Why silica is called flint--history rant?
> Flint is a common, naturally occurring form of silica found as nodules
> and seams in limestone in Great Britain and Europe. Unlike quartz, flint
> contains significant amounts of impurities including calcium, sometimes
> magnesium. I know I'm not the only one to post this. I've read it here
> before, too. At one time flint was the purest, most readily available
> form
> of silica available to potters who first brought pottery making to our
> shores. Flint is very uncommon in North America. However, the word stuc=
k
> and the label flint has now been broadened here in the US and Canada to
> embrace a lot of sources of relatively pure silica. Here flint is a
> synonym
> for ground quartz.
> Lest you think this is all simple, pity the poor geologist who also has
> to
> deal with the question, "What is flint?" For geologists the line between
> flint--an impure, dense, hard, opaque silicate mineral classified as a
> chert
> --and chert itself is a subject of ongoing debate. We aren't the only
> ones
> who can be anal about words.
> Good potting,
> Dave Finkelnburg
> http://www.mattanddavesclays.com
>
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