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Medieval Stained Glass
Medieval stained glass is the coloured and painted glass of medieval Europe from the 10th century to the 16th century. For much of this period stained glass windows were the major pictorial art form, particularly in northern France, Germany and England, where windows tended to be larger than in southern Europe (in Italy, for example, frescos were more common). In some countries, such as Sweden and England, only a small number of original stained windows has survived to this day. Stained glass windows were used predominantly in churches, but were also found in wealthy domestic settings and public buildings such as town halls, though surviving examples of secular glass are very rare indeed. Stained glass windows were used in churches to enhance their beauty and to inform the viewer through narrative or symbolism. The subject matter was generally religious in churches, though "portraits" and heraldry were often included, and many narrative scenes give valuable insights into the med ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Middle Ages
In the history of Europe, the Middle Ages or medieval period lasted approximately from the late 5th to the late 15th centuries, similar to the post-classical period of global history. It began with the fall of the Western Roman Empire and transitioned into the Renaissance and the Age of Discovery. The Middle Ages is the middle period of the three traditional divisions of Western history: classical antiquity, the medieval period, and the modern period. The medieval period is itself subdivided into the Early, High, and Late Middle Ages. Population decline, counterurbanisation, the collapse of centralized authority, invasions, and mass migrations of tribes, which had begun in late antiquity, continued into the Early Middle Ages. The large-scale movements of the Migration Period, including various Germanic peoples, formed new kingdoms in what remained of the Western Roman Empire. In the 7th century, North Africa and the Middle East—most recently part of the Eastern Ro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pliny The Elder
Gaius Plinius Secundus (AD 23/2479), called Pliny the Elder (), was a Roman author, naturalist and natural philosopher, and naval and army commander of the early Roman Empire, and a friend of the emperor Vespasian. He wrote the encyclopedic ''Naturalis Historia'' (''Natural History''), which became an editorial model for encyclopedias. He spent most of his spare time studying, writing, and investigating natural and geographic phenomena in the field. His nephew, Pliny the Younger, wrote of him in a letter to the historian Tacitus: Among Pliny's greatest works was the twenty-volume work ''Bella Germaniae'' ("The History of the German Wars"), which is no longer extant. ''Bella Germaniae'', which began where Aufidius Bassus' ''Libri Belli Germanici'' ("The War with the Germans") left off, was used as a source by other prominent Roman historians, including Plutarch, Tacitus and Suetonius. Tacitus—who many scholars agree had never travelled in Germania—used ''Bella Germani ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
X-ray Fluorescence
X-ray fluorescence (XRF) is the emission of characteristic "secondary" (or fluorescent) X-rays from a material that has been excited by being bombarded with high-energy X-rays or gamma rays. The phenomenon is widely used for elemental analysis and analytical chemistry, chemical analysis, particularly in the investigation of metals, glass, ceramics and building materials, and for research in geochemistry, forensic science, archaeology and art objects such as paintings. Underlying physics When materials are exposed to short-wavelength X-rays or to gamma rays, ionization of their component atoms may take place. Ionization consists of the ejection of one or more electrons from the atom, and may occur if the atom is exposed to radiation with an energy greater than its ionization energy. X-rays and gamma rays can be energetic enough to expel tightly held electrons from the inner atomic orbital, orbitals of the atom. The removal of an electron in this way makes the electronic structu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Forest Glass
Forest glass (''Waldglas'' in German) is late medieval glass produced in northwestern and central Europe from approximately 1000–1700 AD using wood ash and sand as the main raw materials and made in factories known as glasshouses in forest areas.Tait, H., 1991. It is characterized by a variety of greenish-yellow colors, the earlier products often being of crude design and poor quality, and was used mainly for everyday vessels and increasingly for ecclesiastical stained glass windows. Its composition and manufacture contrast sharply with Roman and pre-Roman glassmaking centered on the Mediterranean and contemporaneous Byzantine and Islamic glass making to the east. History While under Roman rule, the raw materials and manufacturing methods of northern Europe were those of the Roman tradition, using the mineral Natron. For several centuries after the fall of the Western Roman Empire, around 450 AD, recycling of Roman glass formed the major part of the local industry and glassma ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Copper Oxide (other)
Copper oxide is a compound from the two elements copper and oxygen. Copper oxide may refer to: * Copper(I) oxide (cuprous oxide, Cu2O) * Copper(II) oxide (cupric oxide, CuO) * Copper peroxide (CuO2) * Copper(III) oxide (Cu2O3) * Copper(IV) oxide Copper is a chemical element with the symbol Cu (from la, cuprum) and atomic number 29. It is a soft, malleable, and ductile metal with very high thermal and electrical conductivity. A freshly exposed surface of pure copper has a pinkish-or ... (CuO2) References {{Authority control Copper compounds ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
England YorkMinster JesseTree C1170
England is a country that is part of the United Kingdom. It shares land borders with Wales to its west and Scotland to its north. The Irish Sea lies northwest and the Celtic Sea to the southwest. It is separated from continental Europe by the North Sea to the east and the English Channel to the south. The country covers five-eighths of the island of Great Britain, which lies in the North Atlantic, and includes over 100 smaller islands, such as the Isles of Scilly and the Isle of Wight. The area now called England was first inhabited by modern humans during the Upper Paleolithic period, but takes its name from the Angles, a Germanic tribe deriving its name from the Anglia peninsula, who settled during the 5th and 6th centuries. England became a unified state in the 10th century and has had a significant cultural and legal impact on the wider world since the Age of Discovery, which began during the 15th century. The English language, the Anglican Church, and English law—th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Manganese Oxide
Manganese oxide is any of a variety of manganese oxides and hydroxides.Wells A.F. (1984) ''Structural inorganic chemistry'' 5th edition Oxford Science Publications, . These include * Manganese(II) oxide, MnO * Manganese(II,III) oxide, Mn3O4 * Manganese(III) oxide, Mn2O3 * Manganese dioxide, MnO2 * Manganese(VI) oxide, MnO3 * Manganese(VII) oxide, Mn2O7 Other manganese oxides include Mn5O8, Mn7O12 and Mn7O13. Minerals It may refer more specifically to the following manganese minerals: * Birnessite * Buserite * Hausmannite * Manganite * Manganosite * Psilomelane * Pyrolusite Manganese may also form mixed oxides with other metals : * Bixbyite, a manganese iron oxide mineral * Jacobsite, a manganese iron oxide mineral * Columbite * Tantalite, a mineral group close to columbite * Coltan, a mixture of columbite and tantalite * Galaxite, a spinel mineral * Todorokite Todorokite is a rare complex hydrous manganese oxide mineral with the chemical formula . It was named in 1934 f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Silica
Silicon dioxide, also known as silica, is an oxide of silicon with the chemical formula , most commonly found in nature as quartz and in various living organisms. In many parts of the world, silica is the major constituent of sand. Silica is one of the most complex and most abundant families of materials, existing as a compound of several minerals and as a synthetic product. Notable examples include fused quartz, fumed silica, silica gel, opal and aerogels. It is used in structural materials, microelectronics (as an Insulator (electricity), electrical insulator), and as components in the food and pharmaceutical industries. Structure In the majority of silicates, the silicon atom shows tetrahedral coordination geometry, tetrahedral coordination, with four oxygen atoms surrounding a central Si atomsee 3-D Unit Cell. Thus, SiO2 forms 3-dimensional network solids in which each silicon atom is covalently bonded in a tetrahedral manner to 4 oxygen atoms. In contrast, CO2 is a linear ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Iron Oxide
Iron oxides are chemical compounds composed of iron and oxygen. Several iron oxides are recognized. All are black magnetic solids. Often they are non-stoichiometric. Oxyhydroxides are a related class of compounds, perhaps the best known of which is rust. Iron oxides and oxyhydroxides are widespread in nature and play an important role in many geological and biological processes. They are used as iron ores, pigments, catalysts, and in thermite, and occur in hemoglobin. Iron oxides are inexpensive and durable pigments in paints, coatings and colored concretes. Colors commonly available are in the "earthy" end of the yellow/orange/red/brown/black range. When used as a food coloring, it has E number E172. Stoichiometries Iron oxides feature as ferrous ( Fe(II)) or ferric ( Fe(III)) or both. They adopt octahedral or tetrahedral coordination geometry. Only a few oxides are significant at the earth's surface, particularly wüstite, magnetite, and hematite. * Oxides of FeII ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Crown Glass (window)
Crown glass was an early type of window glass. In this process, glass was blown into a "crown" or hollow globe. This was then transferred from the blowpipe to a punty and then flattened by reheating and spinning out the bowl-shaped piece of glass (bullion) into a flat disk by centrifugal force, up to 5 or 6 feet (1.5 to 1.8 metres) in diameter. The glass was then cut to the size required. The thinnest glass was in a band at the edge of the disk, with the glass becoming thicker and more opaque toward the center. Known as a bullseye, the thicker center area around the pontil mark was used for less expensive windows. To fill large window spaces with the best glass, many small diamond shapes were cut from the edge of the disk, and then some might be halved into triangles. These were mounted in a lead lattice work and fitted into the window frame. Crown glass was one of the two most common processes for making window glass until the 19th century. The other was blown plate. Crown ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cylinder Blown Sheet
Cylinder blown sheet is a type of hand- blown window glass. It is created with a similar process to broad sheet, but with the use of larger cylinders. In this manufacturing process glass is blown into a cylindrical iron mold. The ends are cut off and a cut is made down the side of the cylinder. The cut cylinder is then placed in an oven where the cylinder unrolls into a flat glass sheet. William J. Blenko used this method in the early 1900s to make stained glass. The result is much larger panes and improved surface quality over broad sheet, although still containing some imperfections. These imperfect panes have led to the misconception that glass is actually a high-viscosity fluid at room temperature, which is not the case. This method caused surface damages on the glass due to the flattening and moving, and the sheet therefore had to be ground and polished. In 1839 the Chance Brothers invented the patent plate process where the glass plate was placed on a wet piece of leather and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
