Alum, in chemistry, is a term given to the crystallized double sulfates of the typical formula M+2SO4·M3+2(SO4)3·24H2O, where M+ is the sign of an alkali metal (lithium, sodium, potassium, rubidium, or caesium), and M3+ denotes one of the trivalent metals (typically aluminium, chromium, or iron (III)). The ammonium ion (NH4+) also occurs in the M+ position. These salts are employed in ...

Including:

• Alum - Alchemical and later discoveries and uses
• Alum - Pliny's writings
• Alum - Alum from alunite
• Alum - Alum from clays or bauxite
• Alum - Types of alum
• Alum - Soda alum
• Alum - Chrome alum
• Alum - Ammonium alum
• Alum - Alum solubility
• Alum - Uses

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Coal comes in four main types or ranks: lignite or brown coal, bituminous coal or black coal, anthracite and graphite. Each type of coal has a certain set of physical parameters which are mostly controlled by moisture, volatile content (in terms of aliphatic or aromatic hydrocarbons) and carbon content. Moisture Moisture is an important proerty of coal, as all coals are mined wet. Groundwater and other extraneous moisture is known as adventitious moisture and is readily evaporated. Moisture held within the c ...

See also:

Coal assay, Coal assay - Chemical properties of coal, Coal assay - Physical and Mechanical Properties, Coal assay - Special Combustion Tests

Read more here: » Coal assay: Encyclopedia II - Coal assay - Chemical properties of coal

Collecting fossils can be a very relaxing and often rewarding hobby. There are no special rules about where one may find fossils, and you can find fossils in many places where sedimentary rocks are exposed, such as clays, shales, limestones, and sandstones. Only certain sedimentary rocks will yield fossils, and they are often concentrated along particular bedding planes within the rocks. Collecting fossils - Finding fossils. Fossils are not to be found in areas of igneous rock (except in some beds between l ...

Including:

• Collecting fossils - Finding fossils
• Collecting fossils - Collecting ethics
• Collecting fossils - Field collecting
• Collecting fossils - Equipment
• Collecting fossils - Preservation and documentation

Read more here: » Collecting fossils: Encyclopedia - Collecting fossils

Ammonites are an extinct group of marine animals (subclass Ammonoidea) in the phylum Mollusca and class Cephalopoda. Their closest living relative is probably not the modern Nautilus, whom they resemble, but rather the Subclass Coleoidea (octopus, squid, and cuttlefish). Their fossil shells take the form of flat spirals (though there are some rarer helically spiraled and non-spiraled forms, called heteromorphs) and are responsible for the animals' name as they somewhat resemble a tightly coiled ram's horn (the god Ammon was com ...

Including:

• Ammonite - Classification
• Ammonite - Life
• Ammonite - Shell anatomy and diversity
• Ammonite - Basic shell anatomy
• Ammonite - Sexual dimorphism
• Ammonite - Variations in shape
• Ammonite - The aptychus
• Ammonite - Size
• Ammonite - Ammonite distribution
• Ammonite - Trivia
• Ammonite - References and further reading

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Common flax (also known as linseed) is a member of the Linaceae family, which includes about 150 plant species widely distributed around the world. Some of them are grown in domestic flower beds, as flax is one of the few truly blue flowers. (Most "blue" flowers are really a shade of purple.) Under the dwindling Cronquist system of classifying the flowering plants, flax and related plants were placed in an order Linales. Modern classifications place them in the order Malpighiales. Flax is a Natural Fiber that belo ...

Including:

• Flax - Usage of Flax
• Flax - Cultivating flax
• Flax - Dressing flax
• Flax - Trivia

Read more here: » Flax: Encyclopedia - Flax

Panspermia is the hypothesis that the seeds of life are ubiquitous in the universe, that they may have delivered life to Earth, and that they may deliver or have delivered life to other habitable bodies; also the process of such delivery. Exogenesis is a related, but less radical, hypothesis that simply proposes life originated elsewhere in the universe and was transferred to Earth, with no prediction about how widespread life is. The term "panspermia" is more well-known, however, and tends to be used in reference to wha ...

Including:

• Panspermia - The panspermia theory
• Panspermia - Evidence
• Panspermia - Narrow time window for geogenesis
• Panspermia - Extremophiles
• Panspermia - Wider range of potential habitats for life
• Panspermia - Evidence of extraterrestrial life
• Panspermia - Objections to panspermia and exogenesis
• Panspermia - Directed panspermia
• Panspermia - Science fiction

Read more here: » Panspermia: Encyclopedia - Panspermia

Chlorite is a group of phyllosilicate minerals often classified as clays. Chlorites can be described by the following four endmembers based on the metals: Mg, Fe, Ni, and Mn. Clinochlore: (Mg5Al)(AlSi3)O10(OH)8 Chamosite: (Fe5Al)(AlSi3)O10(OH)8 Nimite: (Ni5Al)(AlSi3)O10(OH)8 Pennantite: (Mn,Al)6(Si ...

Including:

• Chlorite group - Chlorite structure
• Chlorite group - Occurrence
• Chlorite group - Members of the Chlorite group:

Read more here: » Chlorite group: Encyclopedia - Chlorite group

Coal assay techniques are specific analytical methods designed to measure the particlar physical and chemical properties of coals. These methods are used primarily to determine the suitability of coal for coking, power generation or for iron ore smelting in the manufacture of steel. Coal assay - Chemical properties of coal. Coal comes in four main types or ranks: lignite or brown coal, bituminous coal or black coal, anthracite and graphite. Each type of coal has a certain set of physical parameters which ar ...

Including:

• Coal assay - Chemical properties of coal
• Coal assay - Physical and Mechanical Properties
• Coal assay - Special Combustion Tests

Read more here: » Coal assay: Encyclopedia - Coal assay

Coal is a fossil fuel extracted from the ground by underground mining or open-pit mining (strip mining). It is a readily combustible black or brownish-black sedimentary rock. It is composed primarily of carbon along with assorted other elements, including sulfur. Often associated with the Industrial Revolution, coal remains an enormously important fuel and is the largest single source of electricity world-wide. In the United States, for example, the burning of coal generates 50% of the electricity consumed. Coal - Etymol ...

Including:

• Coal - Etymology and folklore
• Coal - Composition
• Coal - Creation
• Coal - Types of coal
• Coal - Uses
• Coal - Coal as fuel
• Coal - Coking and use of coke
• Coal - Harmful effects of coal burning
• Coal - Coal fires
• Coal - World coal reserves

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Alistair Burt, Nadine Dorries, Patrick Hall, Kelvin Hopkins, Margaret Moran, Andrew Selous Bedford Mid Bedfordshire South Bedfordshire Luton (Unitary) Bedfordshire is a county in England and forms part of the East of England region. Its county town is Bedford. It borders Cambridgeshire, Northamptonshire, Buckinghamshire (with the Borough of Milton Keynes) and Hertfordshire. The highest elevation point is 243 metres/797 feet, on the Dunstable Downs i ...

Including:

• Bedfordshire - History
• Bedfordshire - Geography and geology
• Bedfordshire - Transport
• Bedfordshire - Roads
• Bedfordshire - Railways
• Bedfordshire - Waterways
• Bedfordshire - Air
• Bedfordshire - Towns and villages
• Bedfordshire - Places of interest

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In geography, a desert is a landscape form or region that receives little precipitation - less than 250 mm per year. Deserts have a reputation for supporting very little life. Compared to wetter regions this may be true, although upon closer examination, deserts often harbor a wealth of life that usually remains hidden (especially during the daylight) to preserve moisture. Approximately one-third of Earth's land surface is desert. (See a map of the world's non-polar deserts, http: ...

Including:

• Desert - Types of desert
• Desert - Montane deserts
• Desert - Desert features
• Desert - Soils
• Desert - Vegetation
• Desert - Water
• Desert - Mineral resources
• Desert - List of deserts
• Desert - Americas
• Desert - Africa
• Desert - Asia-Pacific

Read more here: » Desert: Encyclopedia - Desert

Gibbsite, Al(OH)3, is an important ore of aluminium and is one of three minerals that make up the rock bauxite. Bauxite is often thought of as a mineral but is really a rock composed of aluminium oxide and hydroxide minerals such as gibbsite, boehmite (AlO(OH)), and diaspore (HAlO2), as well as clays, silt, and iron oxides and hydroxides. Bauxite is a laterite, a rock formed from intense weathering environments such as foun ...

Read more here: » Gibbsite: Encyclopedia - Gibbsite

Biostimulation involves the modification of the environment to stimulate existing bacteria capable of bioremediation. This can be done by addition of various forms of limiting nutrients, such as phosphorus, nitrogen, or carbon (e.g. in the form of molasses). Additives are usually added to the subsurface through injection wells, although injection well technology for biostimulation purposes is still emerging. Removal of the contaminated material is also an option, albeit and expensive one. ...

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The schists form a group of medium-grade metamorphic rocks, chiefly notable for the preponderance of lamellar minerals such as micas, chlorite, talc, hornblende, graphite, and others. Quartz often occurs in drawn-out grains to such an extent that a particular form called quartz schist is produced. By definition, schist contains more than 50% platy and elongated minerals, often finely interleaved with quartz and feldspar. The individual mineral grains in schist, drawn out into flaky scales by heat and pressure, can be seen by th ...

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Sandstone is a sedimentary rock composed mainly of sand-size mineral or rock grains. Most sandstone is comprised of quartz and/or feldspar because these are the most common minerals in earth's crust. Like sand, sandstone may be any color, but the most common colors are tan, brown, yellow, red, gray, and white. Since sandstone beds often form highly visible cliffs and other topographic features, certain colors of sandstone may be strongly identified with certain regions. For instance, much of the North Ame ...

Including:

• Sandstone - Origins
• Sandstone - Types of sandstone
• Sandstone - Basic References

Read more here: » Sandstone: Encyclopedia - Sandstone

Chalk is a soft, white, porous form of limestone composed of the mineral calcium carbonate. It is relatively resistant to erosion and slumping compared to the clays that it is usually associated with, and so forms tall steep cliffs where chalk ridges meet the sea. Chalk hills, known as chalk downland, usually form where bands of chalk reach the surface at an angle. Chalk is formed in shallow waters by the gradual accumulation of the calcite mineral remains of micro-organisms over millions of years. Embedded fli ...

Read more here: » Chalk: Encyclopedia - Chalk

Weathering is the process of decomposition and/or disintegration of rocks, soils and their minerals through natural, chemical, and biological processes that is, in place. It is not to be confused with erosion, which is the movement of rocks and/or weathering products by water, wind, ice or gravity. The breakdown products, after chemical weathering of rock and sediment minerals and the leaching out of the more soluble parts, when combined with decaying organic material, is called soil. The mineral content of the soil is determin ...

Including:

• Weathering - Mechanical Physical Weathering
• Weathering - Exfoliation
• Weathering - Freeze-thaw
• Weathering - Pressure release
• Weathering - Salt-crystal growth
• Weathering - Organic Activity
• Weathering - Abrasion
• Weathering - Chemical Weathering
• Weathering - Carbonation-solution
• Weathering - Hydration
• Weathering - Hydrolysis
• Weathering - Oxidation
• Weathering - Acids rain and plants

Read more here: » Weathering: Encyclopedia - Weathering

Till is an unsorted glacial sediment. Glacial drift is a general term for the coarsely graded and extremely heterogeneous sediments of glacial origin. Glacial till is that part of glacial drift which was deposited directly by the glacier. It may vary from clays to mixtures of clay, sand, gravel and boulders. A particularly sticky form of clay till is called gumbo. Clay in till may form balls called till balls. If a till ball rolls around in a stream and picks up rocks from the bed of the stream and becomes covered wi ...

Including:

• Till - Tillite
• Till - Types of till

Read more here: » Till: Encyclopedia - Till

Carbon is a chemical element in the periodic table that has the symbol C and atomic number 6. An abundant nonmetallic, tetravalent element, carbon has several allotropic forms: Diamond (hardest known natural mineral). Structure: each atom is bonded tetrahedrally to four others, making a 3-dimensional network of puckered six-membered rings of atoms. Graphite (one of the softest substances). Structure: each atom is bonded trigonally to three other atoms, making a 2-dimensional network of flat s ...

Including:

• Carbon - Notable characteristics
• Carbon - Applications
• Carbon - Other uses
• Carbon - History and Etymology
• Carbon - Allotropes
• Carbon - Occurrence
• Carbon - Organic compounds
• Carbon - Carbon chains
• Carbon - Carbon cycle
• Carbon - Isotopes
• Carbon - Precautions

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Korean pottery - Chinese influences. With many scholars, and trade missions sent to China, the Koreans who returned brought back many fine samples of the best of Chinese potters' wares, and may have indeed as well studied in China, or brought back Chinese clay as ballast to make Korean artefacts. The styles of China, the forms, approaches, the glazes and glazing methods, a ...

See also:

Korean pottery, Korean pottery - Early history, Korean pottery - Chinese influences, Korean pottery - Three Kingdoms pottery, Korean pottery - Silla Era pottery, Korean pottery - Goryeo Dynasty, Korean pottery - Joseon Dynasty pottery, Korean pottery - Occupied Korea and Japanese restraints, Korean pottery - After 1945, Korean pottery - Contemporary pottery, Korean pottery - Kilns, Korean pottery - Centers for studying Korean pottery

Read more here: » Korean pottery: Encyclopedia II - Korean pottery - Early history