Ball clays are kaolinitic sedimentary clays, that commonly consist of 20-80% kaolinite, 10-25% mica, 6-65% quartz. Localized seams in the same deposit have variations in composition, including the quantity of the major minerals, accessory minerals and carbonaceous materials such as lignite. They are fine-grained and plastic in nature.
Ball clays are relatively scarce deposits due to the combination of geological factors needed for their formation and preservation. They are mined in parts of the Eastern United States and from three sites in Devon and Dorset in South West England. They are commonly used in the construction of many ceramic articles, where their primary role is to either to impart plasticity or to aid rheological stability during the shaping processes.
Read more about Ball Clay: History
Other articles related to "ball clay, clay, balls, ball clays, ball":
... Purbeck Ball Clay has been used for thousands of years, but large scale commercial extraction began in the middle of the 18th century and continues today ... Originally the clay was taken by pack horse to wharves on the River Frome and the south side of Poole Harbour ... This was the Middlebere Plateway, which connected clay workings owned by the London Merchant Benjamin Fayle in the Corfe Castle area, to a wharf on Middlebere ...
... Purbeck Ball Clay is a concentration of ball clay found on the Isle of Purbeck in the English county of Dorset ...
... The name "ball clay" is believed to derive from the time when the clay was mined by hand ... and during transport the corners of the cubes became rounded off leaving "balls" ... The ceramic use of ball clays in Britain dates back to at least the Roman era ...
... Wares can be constructed by hand from coils of clay, combining flat slabs of clay, or pinching solid balls of clay or some combination of these ... are often joined together with the aid of slip, an aqueous suspension of clay body and water ... coming from the Old English word thrawan which means to twist or turn, a ball of clay is placed in the centre of a turntable, called the wheel-head, which the potter rotates with a ...
Famous quotes containing the words clay and/or ball:
“The earth is covered thick with other clay,
Which her own clay shall cover, heaped and pent,
Rider and horse,friend, foe,in one red
—George Gordon Noel Byron (17881824)
“The world was a huge ball then, the universe a might harmony of ellipses, everything moved mysteriously, incalculable distances through the ether.
We used to feel the awe of the distant stars upon us. All that led to was the eighty-eight naval guns, ersatz, and the night air-raids over cities. A magnificent spectacle.
After the collapse of the socialist dream, I came to America.”
—John Dos Passos (18961970)