These minerals can be classified on the basis of variations of chemical composition and atomic structure into nine groups: (1) kaolin-serpentine (kaolinite, halloysite, lizardite, chrysotile), (2) pyrophyllite-talc, (3) mica (illite, glauconite, celadonite), (4) vermiculite, (5) smectite (montmorillonite, nontronite.

Clay minerals are an important group of minerals because they are among the most common products of chemical weathering, and thus are the main constituents of the fine-grained sedimentary rocks called mudrocks (including mudstones, claystones, and shales).

Clay comes from the ground, usually in areas where streams or rivers once flowed. It is made from minerals, plant life, and animals—all the ingredients of soil. Over time, water pressure breaks up the remains of flora, fauna, and minerals, pulverising them into fine particles.

Clay minerals are excellent as clarifiers, absorption and adsorption materials. They are used in many industrial applications such as paper, paint, petroleum, ceramic, cement, adhesive, asphalt, and food and health-care industry due to their versatility, abundance, and low cost [1, 2].

Illite

The small size of the particles and their unique crystal structures give clay materials special properties. These properties include: cation exchange capabilities, plastic behaviour when wet, catalytic abilities, swelling behaviour, and low permeability.

Clay minerals include the following groups:

• Kaolin group which includes the minerals kaolinite, dickite, halloysite, and nacrite (polymorphs of Al.
• Smectite group which includes dioctahedral smectites, such as montmorillonite, nontronite and beidellite, and trioctahedral smectites, such as saponite.

They are sheet silicate minerals like micas. Quartz chemically weathers only very, very slowly because of its high stability. It is mostly just broken down into small, sand-sized and smaller particles….

Clay minerals refers to a group of hydrous aluminosili- cates that predominate the clay-sized (<2 |xm) fraction of soils. Primary minerals form at elevated temperatures and pressures, and are usually derived from igneous or metamorphic rocks.

Clay minerals most commonly form by prolonged chemical weathering of silicate-bearing rocks. They can also form locally from hydrothermal activity. Smectite forms by weathering of igneous rock under alkaline conditions, while gibbsite forms by intense weathering of other clay minerals.

Clays are phyllosilicates (“phyllo” meaning sheet), and they are generally classified into three main groups: kaolin, micas, and smectites [15]. Smectites (“smectos” meaning soap) are expandable (swelling) clays. They are made up of parallel aluminosilicate sheets, where the particle size is in the micron range.

The phyllosilicates, or sheet silicates, are an important group of minerals that includes the micas, chlorite, serpentine, talc, and the clay minerals. The basic structure of the phyllosilicates is based on interconnected six member rings of SiO4-4 tetrahedra that extend outward in infinite sheets.

Clays and clay minerals are found mainly on or near the surface of the Earth. Figure 1. Massive kaolinite deposits at the Hilltop pit, Lancaster County, South Carolina; the clays formed by the hydrothermal alteration and weathering of crystal tuff.

sedimentary rock

Depending on the temperature, cobalt carbonate can be a light blue with higher concentrations being near black. Nickle can create a variety of colors as can manganese and other oxides and carbonates.

Kato Polyclay

Clay Soil is a heavy soil type that benefits from high nutrients. Clay soils remain wet and cold in winter and dry out in summer. These soils are made of over 25 percent clay, and because of the spaces found between clay particles, clay soils hold a high amount of water.

Clay feels sticky when wet. Water drains very slowly through clay soil. Therefore, clay soil remains saturated after a heavy rain. When this happens, there is little air in the soil, and plant roots cannot find oxygen..

Mineral and raw material ​​resources and everyday life Clay is used to make bricks and roofing tiles, and as an additive in cat litter and paint, for example. Limestone is used in fertiliser, cement, paint, etc.

While there are thousands of clay bodies available for purchase, the 3 basics types are porcelain, stoneware and earthenware.