In our weekly ‘Material Alchemy’ lecture we were encourage to look into clay suppliers and the description for their clays.
One of the most widely used clays in the CSAD are from POTCLAYS. Established in 1932 as a clay mining company in Brownhills, South Staffordshire; it now creates premium-quality clay bodies with a worldwide reputation.
The supplier has very good website with large selection of products for potters, however the only technical information for their clays is the recommended firing temperature; which for the clays used in CSAD is 1150°C – 1290°C for Buff Stoneware and 1160°C – 1300°C for White St Thomas.
Valentine Clays is another British family manufacturer of clays, from which the CSAD gets its Red Terracotta clays.
The website also states the basic properties such as texture, appropriate use, colour and firing range:1080°C – 1180°C
I haven’t manage to find any more first hand manufacturers of clay with good website and online shop.
However COMMERCIAL CLAY LTD is another manufacturer from Stoke-on-Trend established in 1982. Its old-fashioned website shows all of their clays with some data sheets information.
I searched for suppliers in Slovakia too, finding only one KERAMIKA BIELA HORA s.r.o. manufacturing a multi-purpose clay, however the website doesn’t even inform if it’s stoneware or earthenware.
Most of the suppliers buy the clays produced in Germany or other European countries.
Local clay depositories and previous mining activity such as in Pozdisovce has apparently been closed, mostly due to low competitiveness and demand, as well as bad business practices from Communist era.