Graphite. A graphite stick, also known as a graphite block or graphite pencil, is a drawing tool used in art. It is made of pure graphite and has a rectangular or square shape, similar to a bar of soap or a block of clay. Graphite sticks come in various grades, ranging from soft to hard, with the softness or hardness indicated by a number and letter system. The most common grades are 2B, 4B, and 6B, with 2B being the softest and 6B being the hardest. Graphite sticks are used for creating large areas of tone, shading, and texture in drawings. They are particularly useful for creating broad, sweeping marks and for covering large areas quickly. To use a graphite stick, the artist holds it like a piece of chalk or a pastel and applies it to the paper with light or heavy pressure, depending on the desired effect. The stick can be sharpened to a point for more detailed work, or used on its side for broader marks. Graphite sticks can be blended with a variety of tools, such as tortillons, blending stumps, or even the artist's fingers, to create smooth transitions between tones. They can also be used in combination with other drawing media, such as graphite pencils, charcoal, and pastels, to create a range of textures and effects. Graphite sticks are popular among artists for their versatility and ability to create a wide range of tones and textures. They are often used in sketching and preliminary drawing, as well as in finished artwork. Some artists also use graphite sticks to create abstract or expressive drawings, taking advantage of the bold, gestural marks that can be achieved with the medium. Graphite is a crystalline form of the element carbon. It consists of stacked layers of graphene. Graphite occurs naturally and is the most stable form of carbon under standard conditions. Synthetic and natural graphite are consumed on a large scale for uses in pencils, lubricants, and electrodes. Under high pressures and temperatures it converts to diamond. It is a good conductor of both heat and electricity. The principal types of natural graphite, each occurring in different types of ore deposits, are Crystalline small flakes of graphite occurs as isolated, flat, plate-like particles with hexagonal edges if unbroken. When broken, the edges can be irregular or angular;. Amorphous graphite: very fine flake graphite is sometimes called amorphous;. Lump graphite occurs in fissure veins or fractures and appears as massive platy intergrowths of fibrous or acicular crystalline aggregates, and is probably hydrothermal in origin. Highly ordered pyrolytic graphite refers to graphite with an angular spread between the graphite sheets of less than 1°. The name graphite fiber is sometimes used to refer to carbon fibers or carbon fiber-reinforced polymer. Synthetic graphite is a material consisting of graphitic carbon which has been obtained by graphitizing of non-graphitic carbon, by chemical vapor deposition from hydrocarbons at temperatures above 2,500 K, by decomposition of thermally unstable carbides or by crystallizing from metal melts supersaturated with carbon. Biographite is a commercial product proposal for reducing the carbon footprint of lithium, iron, phosphate batteries. It is produced from forestry waste and similar byproducts by a company in New Zealand using a novel a process called thermo-catalytic graphitisation which project is supported by grants from interested parties including a forestry company in Finland and a battery maker in Hong Kong Graphite occurs in metamorphic rocks as a result of the reduction of sedimentary carbon compounds during metamorphism. It also occurs in igneous rocks and in meteorites. Minerals associated with graphite include quartz, calcite, micas and tourmaline. The principal export sources of mined graphite are in order of tonnage: China, Mexico, Canada, Brazil, and Madagascar. In meteorites, graphite occurs with troilite and silicate minerals. Small graphitic crystals in meteoritic iron are called cliftonite. Some microscopic grains have distinctive isotopic compositions, indicating that they were formed before the Solar System.
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