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Clay Production Cycle

From the ground... to you... and back home as finished pots.
Below you will see how the clay is mined and refined before going to you... then the clay returns to Sheffield in the form of your finished pots in our Sheffield Showroom and online store :
Read about our pottery buy-back

WGBY presents "Making it Here" the story of Sheffield Pottery and tour of how your clay is made:

Clay pit mineNatural Sheffield Clay is mined on our property from as seen at one of the open clay pits.

The Sheffield Clay deposit is located in Sheffield, Massachusetts, on U.S. Route 7 in the Southwest corner of Berkshire County. It is situated in the Housatonic River Valley, 60 miles southeast of Albany, New York and 60 miles northwest of Hartford, Connecticut. The deposit is approximately 300 feet deep and is located on a 16 acre site.
Our warehouse and production facility includes a 3000 square foot bulk handling area for use in processing our Sheffield Clay.
Special properties of this clay are its plasticity, fired color and unique particle size. The raw clay is a pure clay, with no stones, sticks or other contaminants. Our tested formulas blend Sheffield Clay with other more common clays, resulting in a distinct, high quality range of clay bodies unequaled in the Northeast.
Clay dryingThe Natural clay is then piled and left in the sun to begin drying process.
Clay at the hammermillThe Clay is taken under cover for additional drying before passing into the hammermill to be powdered.
Clay Batching systemThe powered dry clay is precisely portioned through our custom Batching System. This system is accurate to 0.5 grams per ton of dry materials ensuring the consistency of our clay bodies whether we are making one of our stock clays or your own custom formula.

Sheffield Pottery can produce other types of custom formulas for you as well in addition to moist clays. We can mix dry clays, wet or dry glazes, and casting slips to your exact specifications. Please call for information on these services.
Sweco Clay Screening UnitWe have expanded our production line to include additional machinery setting a new standard for the clay industry . There are two basic pieces of equipment in the system, Sweco's new 72" flow through separator and an iron filtration magnet .

THE SWECO UNIT enables us to dry screen the entire batch of clay as it goes through the production process. Problematic materials like fire clay, grog and lizella can be carefully controlled. We have found that normally clean materials like ball clay, flint and feldspar can also have oversized nodules of lignite, wood, paper, stones and other unwanted material. Screening the entire batch will ensure that no contaminants remain. Previously we only screened the fire clay and lizella components of our stoneware bodies. By offering 30, 40, 50, 80 and 100 mesh screens we are finding that many of our earthenware and porcelain customers are benefiting from the process as well. Many of our stock bodies are available screened. Any custom or other stock body can be ordered screened.

THE IRON FILTRATION MAGNET is a four-tier unit made with "rare earth" magnets. As the dry batches cascade through the filter it will trap ferrous metal contaminants that come from processing machinery or the raw clays themselves. This option can be used with or without any mesh screen, and will help eliminate iron spots in the clay.
Clay MixerThe Clay is mixed in our new Eirich Mixer. (Similar to the one shown right) Then it is passed into one of our giant puggers where the moist clay is de-aired before being packaged for shipment.

Standard clay packaging is two 25 lb. plastic bagged slugs in a 50 lb. box. The slugs are either 5” round or 6” square.
By special order, clay may be ordered without boxes, and is shipped on shrink wrapped pallets.
Also available are single round 50 lb. slugs which measure 7” round by 18” long, or slab clay, which is 1” thick by 18” width.
Other sizes and packaging are available by special order - please inquire.

We are happy to reprocess your clay scraps. They must be near working consistency and bagged. We will adjust the clay to your moisture content specifications and completely mix, re-pug and repackage it. Minimum amount is 4000 lbs. The charge is .12 per lb. plus freight each way.
WarehouseDry and moist clays are stored in our temperature controlled warehouse where they wait patiently to be ordered...
Sheffield Pottery TruckYour clay and ceramic supplies ship on our trucks or via UPS.

This year we added another delivery truck with the Cargomaster crane system. One man, one thumb, can deliver a 4000 lb. pallet where you want it!

When we drop off your clay we pick up your pots...

"First unload the boxes of clay from their truck. Then immediately load my finished work right back on the truck! For well over a decade Sheffield Pottery has supplied me with both excellent customer service and the most consistent and finest prepared stoneware clay body.
Furthermore their on site gallery has supported me by selling my wheel thrown functional pottery. John, Diane, Benny, Chris, and all the folks at Sheffield Pottery truly care about their customers!"
-Bob Fishman—Robert Fishman Pottery
Pottery ShowroomFull Circle: The clay returns home to Sheffield as finished pottery:

Many professional Potters take advantage of Our Buy back Program wherein we bring you the clay and then we buy your final product to sell in our Sheffield Showroom and online at our sister site:

If you sell your work wholesale and use our clay or raw materials please click here to read about our Pottery Buy-Back Program.
Read About Our Clay And Raw Material Refining System