I am not sure that Bryn Ellis has quite got this right. Round about 1720,
it was realised that the addition of finely ground flint to a clay body,
gave a much desired whiteness in the finished ware, as well as a greater
firmness and consistency in the clay body, making a thinner ware possible,
as opposed to the heavier earthenware. But flint is exceptionally hard, and
its dust gives ‘Potters Rot’ – Silicosis. Hence the 'grinding' was done
under water.
Benson’ patent of 1726 seems to have first used edge iron runners to do the
crushing under water, then wet grinding in a pan with iron balls, but the
problem with these methods was iron staining in the finished product.
Bensons next patent, of 1732, used wet pan grinding, with a chert floor,
and chert crushing blocks, chert being one stone which was harder than flint.
I would imagine that most chert quarrying/mining took place after 1732. If
you need to know more about wet-pan grinding with chert, visit the
Cheddleton Flint Mill Museum about 4 miles south of Leek in Staffordshire.
>Evan Price <[log in to unmask]>
>wrote:
>
>> One person said on this page that it was used in pottery
>>making. If anyone knows, I would appreciate being told what it is used
>>for in pottery making and how it is prepared for use.
>
>
>Have been away and have just seen the above. Chert was quarried
>extensively in Flintshire from the 1780s to the 1930s and transported to
>the Staffordshire Potteries for use in lining mills for the grinding of
>materials, e.g. bones, for making pottery.
>It was quarried as blocks of various dimensions and used as the fixed
>base of the mill. Softer Derbyshire chert was used in the revolving part
>of the mill. One quarry owner claimed that, because of the need for
>exactness in size and shape of the blocks, 90 % of what was quarried
>was waste!. The waste was used by refractory industries of Sheffield.
>More details in my book [see website below]. I understand that the dust
>created in these mills eventually became recognised for its seriously
>harmful effects on the health of millworkers, and was phased out.
>Bryn Ellis
>[log in to unmask]
>See my site at
>http://www.helygain.freeserve.co.uk/halkyn.htm
>
>
>
Stafford M Linsley
Lecturer in Industrial Archaeology
The University
Newcastle upon Tyne
England
NE1 7RU
Tel. 0191-222 6795
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