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Prehistoric humans discovered the useful properties of clay and used it for making pottery. Some of the earliest pottery shards have been dated to around 14,000 BCE, [7] and clay tablets were the first known writing medium. [8] Clay is used in many modern industrial processes, such as paper making, cement production, and chemical filtering ...
The main ingredient of the body is clay. Some different types used for pottery include: [16] Kaolin, sometimes referred to as china clay, is a key ingredient in porcelain, which was first used in China around the 7th and 8th centuries. [17] Ball clay: An extremely plastic, fine grained sedimentary clay, which may contain some organic matter.
Sumerian clay tablet, currently housed in the Oriental Institute at the University of Chicago, inscribed with the text of the poem Inanna and Ebih by the priestess Enheduanna, the first author whose name is known [8] The Babylonian Plimpton 322 clay tablet, with numbers written in cuneiform script.
In Chengtoushan, fired bricks were used as flooring for houses. [16] Clay was also used as sewer pipes by the Mesopotamians at around 4000 BC, with the earliest examples found in the Temple of Bel in Babylonia. Latrines in the city of Uruk have raised fired brick foot platforms at around 3200 BC.
Slip is a liquid clay suspension of mineral pigments applied to the ceramics before firing. Slips are typically red, buff, white, and black; however, Nazca culture ceramic artists in Peru perfected 13 distinct colors of slips. They also used a hand-rotated turntable that allowed all sides of a ceramic piece to be painted with ease.
Kaolinite (/ ˈ k eɪ. ə l ə ˌ n aɪ t,-l ɪ-/ KAY-ə-lə-nyte, -lih-; also called kaolin) [5] [6] [7] is a clay mineral, with the chemical composition Al 2 Si 2 O 5 4.It is a layered silicate mineral, with one tetrahedral sheet of silica (SiO 4) linked through oxygen atoms to one octahedral sheet of alumina (AlO 6).
Moulded bricks – These bricks start with raw clay, preferably in a mix with 25–30% sand to reduce shrinkage. The clay is first ground and mixed with water to the desired consistency. The clay is then pressed into steel moulds with a hydraulic press. The shaped clay is then fired at 900–1,000 °C (1,650–1,830 °F) to achieve strength.
The clay mineral montmorillonite has been shown to catalyze the polymerization of RNA in aqueous solution from nucleotide monomers, [29] and the formation of membranes from lipids. [30] In 1998, Hyman Hartman proposed that "the first organisms were self-replicating iron-rich clays which fixed carbon dioxide into oxalic acid and other ...