Steel in the context of Martensite

The European Coal and Steel Community (ECSC) was a European organization created after World War II to integrate Europe's coal and steel industries into a single common market based on the principle of supranationalism which would be governed by the creation of a High Authority made up of appointed representatives from the member states who would not represent their national interest, but would take and make decisions in the general interests of the Community as a whole. It was formally established in 1951 by the Treaty of Paris, signed by Belgium, France, Italy, Luxembourg, the Netherlands, and West Germany and was generally seen as the first step in the process of European integration following the end of the Second World War in Europe. The organization is a spiritual predecessor to the contemporary European Union (EU) as its subsequent enlargement of both members and duties ultimately led to the creation of the EU.

The ECSC was first proposed via the Schuman Declaration by French foreign minister Robert Schuman on 9 May 1950 (commemorated in the EU as Europe Day), the day after the fifth anniversary of the end of World War II, to prevent another war between France and Germany. He declared "the solidarity in production" from pooling "coal and steel production" would make war between the two "not only unthinkable but materially impossible". The Treaty created a common market among member states that stipulated free movement of goods (without customs duties or taxes) and prohibited states from introducing unfair competitive or discriminatory practices.

The Iron Age (c. 1200 – c. 550 BC) is the final epoch of the three historical Metal Ages, after the Copper Age and Bronze Age. It has also been considered as the final age of the three-age division starting with prehistory (before recorded history) and progressing to protohistory (before written history). In this usage, it is preceded by the Stone Age (subdivided into the Paleolithic, Mesolithic and Neolithic) and Bronze Age. These concepts originated for describing Iron Age Europe and the ancient Near East. In the archaeology of the Americas, a five-period system is conventionally used instead; indigenous cultures there did not develop an iron economy in the pre-Columbian era, though some did work copper and silver. Indigenous metalworking arrived in Australia with European contact. Although meteoric iron has been used for millennia in many regions, the beginning of the Iron Age is defined locally around the world by archaeological convention when the production of smelted iron (especially steel tools and weapons) replaces their bronze equivalents in common use.

In Anatolia and the Caucasus, or Southeast Europe, the Iron Age began c. 1300 BC. In the ancient Near East, this transition occurred simultaneously with the Late Bronze Age collapse, during the 12th century BC. The technology soon spread throughout the Mediterranean basin region and to South Asia between the 12th and 11th centuries BC. Its further spread to Central Asia, Eastern Europe, and Central Europe was somewhat delayed, and Northern Europe was not reached until c. the 5th century BC.

Modern architecture, also called modernist architecture, or the modern movement, is an architectural movement and style that was prominent in the 20th century, between the earlier Art Deco and later postmodern movements. Modern architecture was based upon new and innovative technologies of construction (particularly the use of glass, steel, and concrete); the principle of functionalism (i.e. that form should follow function); an embrace of minimalism; and a rejection of ornament.

According to Le Corbusier, the roots of the movement were to be found in the works of Eugène Viollet-le-Duc, while Mies van der Rohe was heavily inspired by Karl Friedrich Schinkel. The movement emerged in the first half of the 20th century and became dominant after World War II until the 1980s, when it was gradually replaced as the principal style for institutional and corporate buildings by postmodern architecture.

Rail transport (also known as train transport) is a means of transport using wheeled vehicles running on tracks, which usually consist of two parallel steel rails. Rail transport is one of the two primary means of land transport, next to road transport. It is used for about 8% of passenger and freight transport globally, thanks to its energy efficiency and potentially high speed. Also, the track spreads the weight of the train which means larger amounts can be carried than with trucks on roads.

Rolling stock on rails generally encounters lower frictional resistance than rubber-tyred road vehicles, allowing rail cars to be coupled into longer trains. Power is usually provided by diesel or electric locomotives. While railway transport is capital-intensive and less flexible than road transport, it can carry heavy loads of passengers and cargo with greater energy efficiency and safety.

An alloy is a mixture of chemical elements of which in most cases at least one is a metallic element, although it is also sometimes used for mixtures of elements; herein only metallic alloys are described. Metallic alloys often have properties that differ from those of the pure elements from which they are made. The vast majority of metals used for commercial purposes are alloyed to improve their properties or behavior, such as increased strength, hardness or corrosion resistance. Metals may also be alloyed to reduce their overall cost, for instance alloys of gold and copper.

In an alloy, the atoms are joined by metallic bonding rather than by covalent bonds typically found in chemical compounds. The alloy constituents are usually measured by mass percentage for practical applications, and in atomic fraction for basic science studies. Alloys are usually classified as substitutional or interstitial alloys, depending on the atomic arrangement that forms the alloy. They can be further classified as homogeneous (consisting of a single phase), or heterogeneous (consisting of two or more phases) or intermetallic. An alloy may be a solid solution of metal elements (a single phase, where all metallic grains (crystals) are of the same composition) or a mixture of metallic phases (two or more solutions, forming a microstructure of different crystals within the metal).

Coal is a combustible black or brownish-black sedimentary rock, formed as rock strata called coal seams. Coal is mostly carbon with variable amounts of other elements, chiefly hydrogen, sulfur, oxygen, and nitrogen. It is a type of fossil fuel, formed when dead plant matter decays into peat which is converted into coal by the heat and pressure of deep burial over millions of years. Vast deposits of coal originate in former wetlands called coal forests that covered much of the Earth's tropical land areas during the late Carboniferous (Pennsylvanian) and Permian times.

Coal is used primarily as a fuel. While coal has been known and used for thousands of years, its usage was limited until the Industrial Revolution. With the invention of the steam engine, coal consumption increased. In 2020, coal supplied about a quarter of the world's primary energy and over a third of its electricity. Some iron and steel-making and other industrial processes burn coal.

Magnitogorsk (Russian: Магнитого́рск, IPA: [məɡnʲɪtɐˈɡorsk], lit. '[city] of the magnetic mountain') is an industrial city in Chelyabinsk Oblast, Russia, on the eastern side of the extreme southern extent of the Ural Mountains by the Ural River. Its population is currently 410,594 (2021 census).

Magnitogorsk was named after Mount Magnitnaya, a geological anomaly that once consisted almost completely of iron ore, around 55% to 60% iron. It is the second-largest city in Russia that is not the administrative centre of any federal subject or district, after Tolyatti. Magnitogorsk contains the largest iron and steel works in the country: Magnitogorsk Iron and Steel Works. The official motto of the city is "the place where Europe and Asia meet", as the city straddles von Strahlenberg's line.

Puddling is the process of converting pig iron to bar (wrought) iron in a coal fired reverberatory furnace. It was developed in England during the 1780s. The molten pig iron was stirred in a reverberatory furnace, in an oxidizing environment to burn the carbon, resulting in wrought iron. It was one of the most important processes for making the first appreciable volumes of valuable and useful bar iron (malleable wrought iron) without the use of charcoal. Eventually, the furnace would be used to make small quantities of specialty steels.

Though it was not the first process to produce bar iron without charcoal, puddling was by far the most successful, and replaced the earlier potting and stamping processes, as well as the much older charcoal finery and bloomery processes. This enabled a great expansion of iron production to take place in Great Britain, and shortly afterwards, in North America. That expansion constitutes the beginnings of the Industrial Revolution so far as the iron industry is concerned. Most 19th century applications of wrought iron, including the Eiffel Tower, bridges, and the original framework of the Statue of Liberty, used puddled iron.

The Treaty of Paris (formally the Treaty establishing the European Coal and Steel Community) was signed on 18 April 1951 by Belgium, France, Italy, Luxembourg, the Netherlands, and West Germany establishing the European Coal and Steel Community (ECSC), which subsequently became part of the European Union. The treaty came into force on 23 July 1952 and expired on 23 July 2002, exactly fifty years after it came into effect.

The treaty was intended to bring diplomatic and economic stability in western Europe after the Second World War. Some of the main enemies during the war were now sharing production of coal and steel, the key resources which previously had been central to the war effort.

Iron is a chemical element; it has symbol Fe (from Latin ferrum 'iron') and atomic number 26. It is a metal that belongs to the first transition series and group 8 of the periodic table. It is, by mass, the most common element on Earth, forming much of Earth's outer and inner core. It is the fourth most abundant element in the Earth's crust. In its metallic state it was mainly deposited by meteorites.

Extracting usable metal from iron ores requires kilns or furnaces capable of reaching 1,500 °C (2,730 °F), about 500 °C (900 °F) higher than that required to smelt copper. Humans started to master that process in Eurasia during the 2nd millennium BC and the use of iron tools and weapons began to displace copper alloys – in some regions, only around 1200 BC. That event is considered the transition from the Bronze Age to the Iron Age. In the modern world, iron alloys, such as steel, stainless steel, cast iron and special steels, are by far the most common industrial metals, due to their mechanical properties and low cost. The iron and steel industry is thus very important economically, and iron is the cheapest metal, with a price of a few dollars per kilogram or pound.

Church architecture refers to the architecture of Christian buildings, such as churches, chapels, convents, and seminaries. It has evolved over the two thousand years of the Christian religion, partly by innovation and partly by borrowing other architectural styles as well as responding to changing beliefs, practices and local traditions. From the Early Christianity to the present, the most significant objects of transformation for Christian architecture and design were the great churches of Byzantium, the Romanesque abbey churches, Gothic cathedrals and Renaissance basilicas with its emphasis on harmony. These large, often ornate and architecturally prestigious buildings were dominant features of the towns and countryside in which they stood. However, far more numerous were the parish churches in Christendom, the focus of Christian devotion in every town and village. While a few are counted as sublime works of architecture to equal the great cathedrals and churches, the majority developed along simpler lines, showing great regional diversity and often demonstrating local vernacular technology and decoration.

Buildings were at first from those originally intended for other purposes but, with the rise of distinctively ecclesiastical architecture, church buildings came to influence secular ones which have often imitated religious architecture. In the 20th century, the use of new materials, such as steel and concrete, has had an effect upon the design of churches.

A spear is a polearm consisting of a shaft, usually of wood, with a pointed head. The head may be simply the sharpened end of the shaft itself, as is the case with fire hardened spears, or it may be made of a more durable material fastened to the shaft, such as bone, flint, obsidian, copper, bronze, iron, or steel. The most common design for hunting and/or warfare, since modern times has incorporated a metal spearhead shaped like a triangle, diamond, or leaf. The heads of fishing spears usually feature multiple sharp points, with or without barbs.

Spears can be divided into two broad categories: those designed for thrusting as a melee weapon (including weapons such as lances and pikes) and those designed for throwing as a ranged weapon (usually referred to as javelins).

The Paus family (pronounced [ˈpæʉs]), also styled de Paus or von Paus, is a Norwegian family that emerged as an aristocratic priestly family from Medieval Oslo in the 16th century. For centuries, it belonged to the "aristocracy of officials," especially in the clergy and legal professions in Upper Telemark. Later generations entered shipping, steel, and banking, becoming steel magnates in Oslo. The family's best-known members are Henrik Ibsen and Ole Paus. The name is recorded in Oslo from the 14th century and likely derives from a metaphorical use of the Middle Low German word for pope—perhaps meaning "the pious one"—reflecting foreign influence and name satire in medieval Oslo.

The priest brothers Hans (1587–1648) and Peder Povelsson Paus (1590–1653) from Oslo have long been known as the family's earliest certain ancestors. In Slekten Paus, Finne-Grønn identified their grandfather as Hans Olufsson (d. 1570), a canon at St Mary's Church who held noble rank and served as a royal priest both before and after the Reformation. Peder Povelsson Paus came to Upper Telemark as parish priest of Vinje in 1618, became provost of Upper Telemark in 1633, and was the ancestor of the extant family; in the 17th century the family also used the name Vind (Wind) after the parish of Vinje. From the 17th to the 19th century, the family were among the foremost of the regional elite, the "aristocracy of officials" in Upper Telemark, where family members served as priests, judges and other officials, often across generations. The family held the district judgeship—the region's chief governmental and judicial office—for 106 years (1668–1774). It was a meritocratic elite defined by education, priesthood, and service to the state, and the apex of the social order of Upper Telemark.

A knife (pl.: knives; from Old Norse knifr 'knife, dirk') is a tool or weapon with a cutting edge or blade, usually attached to a handle or hilt. One of the earliest tools used by humanity, knives appeared at least 2.5 million years ago, as evidenced by the Oldowan tools. Originally made of wood, bone, and stone (such as flint and obsidian), over the centuries, in step with improvements in both metallurgy and manufacturing, knife blades have been made from copper, bronze, iron, steel, ceramic, and titanium. Most modern knives have fixed or folding blades, with styles varying by maker and country.

Knives can serve various purposes. Hunters use a hunting knife, soldiers use the combat knife, scouts, campers, and hikers carry a pocketknife; there are kitchen knives for preparing foods (the chef's knife, the paring knife, bread knife, cleaver), table knife (butter knives and steak knives), weapons (daggers or switchblades), knives for throwing or juggling, and knives for religious ceremony or display (the kirpan).

The history of architecture traces the changes in architecture through various traditions, regions, overarching stylistic trends, and dates. The beginnings of all these traditions is thought to be humans satisfying the very basic need of shelter and protection. The term "architecture" generally refers to buildings, but in its essence is much broader, including fields we now consider specialized forms of practice, such as urbanism, civil engineering, naval, military, and landscape architecture.

Trends in architecture were influenced, among other factors, by technological innovations, particularly in the 19th, 20th and 21st centuries. The improvement and/or use of steel, cast iron, tile, reinforced concrete, and glass helped for example Art Nouveau appear and made Beaux Arts more grandiose.