Biography
Facade of the Cathedral in Siena
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See what "Giovanni Pisano" is in other dictionaries:
- (Giovanni Pisano) (b. circa 1245 50 died after 1314), Italian sculptor and architect of the Proto-Renaissance; see Pisano...
- (Pisano), the nickname of a number of Italian sculptors and architects of the XIII-XIV centuries. Niccolò (Nicola) Pisano (circa 1220 between 1278 1284), sculptor. One of the founders of the Proto-Renaissance. Experienced the influence of late Roman, southern Italian and ... ... Art Encyclopedia
Pisano- Giovanni Pisano. The lower part of the facade of the cathedral. Pisano (Pisano), the nickname of a number of Italian sculptors and architects of the 13th and 14th centuries. The most famous: Niccolo (about 1220 between 1278 1284), one of the founders of the Proto-Renaissance, the creator of plastic ... ... Illustrated Encyclopedic Dictionary
- (Pisano) the name of several medieval artists and artisans from Pisa: Niccolò Pisano Giovanni Pisano (son of the previous one) Andrea Pisano Bonanno Pisano Other personalities by the name of Pisano: Bernardo Pisano composer Leonardo ... ... Wikipedia
- (Pisano) nickname for a number of Italian sculptors and architects of the 13th and 14th centuries. Niccolò (Nicola) P. (about 1220, Apulia, between 1278 and 1284, Tuscany), sculptor. One of the founders of the Proto-Renaissance. Experienced the influence of South Italian and ... ... Great Soviet Encyclopedia
Pisano, Giovanni- (Pisano, Giovanni) Ok. 1245 after 1317. Italian sculptor, son of Niccolo Pisano, one of the leading masters of the so-called. era of Dante and Giotto. Until his death, Niccolo Pisano (1278/1284) worked in his father's workshop, participated in the creation of ... ...
Pisano, Niccolo- (Pisano, Niccolo) Ok. 1215 1278/1284. Italian sculptor 2nd floor. XIII century., One of the leading masters of the so-called. era of Dante and Giotto, which became the beginning of a new stage in the history of Italian and European culture. Biographical information about Niccolo ... ... European Art: Painting. Sculpture. Graphics: Encyclopedia
- (Pisano, Giovanni) (c. 1245/1250 after 1320), Italian sculptor and architect of the proto-Renaissance era; son, student and assistant of Niccolò Pisano. Born in Pisa c. 1245. In 1265 1278 he worked with his father. About 1270 1276 visited France; in his... ... Collier Encyclopedia
Marco Pisano General information ... Wikipedia
Giunta Pisano or Giunta di Capitino (Italian: Giunta Pisano, documented from 1236 to 1266) was an Italian painter. Giunta Pisano's name. "Cross", detail. 1250 54 Bologna, c. San Domenico. The name Giunta di Capitino was found on a painted ... ... Wikipedia
Books
- From icon to painting. At the beginning of the journey. In 2 books. Book 1, Shvartsman Nadim Abramovich, Book 1. Franco-Gothic motifs and Byzantine roots of Italian painting. French Gothic temple architecture and sculpture was perceived in Italy with great reservations that ... Category: Painting, graphics, sculpture Series: Masterpieces of Painting Publisher:
Giovanni Pisano
A student and assistant of Niccolo Pisano, he, like his father, was a sculptor and architect, an original representative of Italian Gothic. He was born around 1245. He began his career in Siena, where he took part in the work on the cathedra ordered by Niccolò for the cathedral (1265-1268).
Later, he helped him in creating the reliefs of the fountain in Perugia (1278), where already in the style of Giovanni there is a departure from his father's classicism to more intense and complex forms for the sake of dramatic transmission of human feelings. It is generally accepted that the emotionality of the images of Giovanni is due to the influence of French Gothic sculpture. Relief of the pulpit of Sant'Andrea in Pistoia. From 1284 to 1296, he worked on the design of the facade of the Siena Cathedral, from perspective portals to numerous statues - the first independent work. In 1297, documents record his stay in Pisa as the chief master of the cathedral. From 1298 to 1301 Giovanni was working on a commission from Pistoia - a pulpit for the church of Sant'Andrea. A little later, the Madonna of the Scrovegni Chapel in Padua appeared, where the views of Our Lady and Christ turned to each other are filled with deep emotionality. From 1302 to 1310 Giovanni was engaged in the new pulpit of the cathedral in Pisa. His last work was the statue of the Madonna and Child in the Chapel of the Holy Belt of the Cathedral in Prato (Madonna dalla cintola, 1317), where the theme of the silent dialogue between the Virgin Mary and Christ again sounds. Shortly after the completion of this work, Giovanni Pisano died.
Fresco in the Church of San Domenico Cimabue in Arezzo. The Florentine school of painting begins with the work of the artist Cenny di Pepo, nicknamed Cimabue. He was born ca. 1240 in Florence and died in Pisa c. 1302. It was formed in line with the Byzantine tradition and the principles embodied in the mosaics of the Florentine Baptistery of San Giovanni.
The very first of his well-known works is the Crucifixion of the Church of San Domenico in Arezzo (c.1268-1271), where a tense expression of a new dramatic sense is already felt. A few years later he completed the altarpiece of Our Lady (Madonna in maesta, Uffizi, Florence). In 1280-1283. Cimabue takes part in the murals of the Upper Church of the Basilica of San Francesco in Assisi: these are the Evangelists on the vault of the cross, the History of Our Lady in the choir, the scenes of the Apocalypse, the Last Judgment and the Crucifixion in the left arm of the transept, the History of St. Peter in the right. These frescoes show a powerful sense of space and dramatic vision. This trend is continued by the Crucifixion (c.1278-1288, Santa Croce Museum, Florence): the use of more nuanced chiaroscuro adds a touch of heightened emotional characterization. Most likely, in the same period, the Maesta was created in the Lower Church of the Basilica in Assisi, where St. Francis is depicted in front of the Mother of God. The last works of the master - the Madonna (Louvre, Paris), the mosaic of St. John the Evangelist (1302, the cathedral in Pisa) - are tangibly influenced by new forms of Pisan sculpture.
Duccio di Buoninsegna
Duccio was born and died in Siena (c. 1255-c. 1318). He was a prominent representative of Sienese painting at the turn of Ducento and Trecento. The sophisticated, musical sense of color achieved by him, which is in a harmonious ensemble with linear rhythms, marks the formation of refined Sienese painting of the 14th century. There are exact dates for only two works: in 1285 he completed a painting identified with the Rucellai Madonna and has long been attributed to Duccio; in 1308, a large double-sided altarpiece of the Maesta was ordered for the Siena Cathedral, completed in 1311. On one side, the Madonna is depicted enthroned, surrounded by angels and saints; on the back, in 26 scenes, Passion Story. In addition, the artist is credited with the Madonna di Crevole (c. 1283-1284, Cathedral Museum, Siena) and the tiny Madonna of the Franciscans (c. 1300, National Pinacothek, Siena).
He became a much more famous sculptor than his father. Giovanni Pisano's style is more free and dynamic, he shows figures in motion and uses various means of dramatization, his sculptures are characterized by sharp turns and angular outlines.
Encyclopedic YouTube
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✪ Niccolò Pisano, Chair of the Pisa Baptistery. Giovanni Pisano, Massacre of the Innocents, pulpit of churches
✪ Andrea Pisano. Reliefs of the Campanile in Florence
✪ Giotto, Cappella del Arena (Scrovegni), Padua, ca. 1305 (Part 1 of 4)
Subtitles
We are looking at the Baptistery in Pisa, a building founded in the middle of the 12th century. It is located in one of the famous places that you may have seen. Here is the leaning Leaning Tower of Pisa. Yes exactly. The famous Leaning Tower of Pisa is actually the bell tower of the cathedral. This building, the baptistery, stands in front of the cathedral. This is how buildings were usually located in the Italian cities of the Late Middle Ages. The cathedral with the baptistery in front of it signifies a certain religious and civil center of the city. For example, we see the same thing in Florence. Yes. And here we see the same layout. Baptisteries were especially important buildings. This is where the children were baptized. This was of great importance in these cities, where life was determined by the Christian faith and rituals. And here, in this place, each person through the rite of baptism was introduced into the Christian community of the city. Therefore, it is understandable why the city government actively decorated this particular place. Usually these places were very richly decorated, looked after, treated with great attention. It was important for such cities. Great, let's go. From an architectural point of view, this is the Middle Ages, right? Going inside, we see ... Inside we see something that anticipates radical changes, in some ways even revolutionary ones. This can be seen when looking at the structure inside the baptistery. This is the pulpit by Niccolò Pisano in the Baptistery of Pisa, completed around 1260. It was on the pulpit that the priest stood during the sermon. Yes. It was necessary to climb the pulpit, and these reliefs are, in fact, a low wall. Here, the eagle supports a small shelf where you can put a book or other text for the priest to read a sermon. So everyone could see and hear him. We see multicolored columns with capitals. Virtues are depicted above the capitals. And above here we see other reliefs, narrative reliefs showing episodes from the life of Christ. They are separated by small columns. I want to draw your attention to a very interesting figure of Fortitude. This is one of the virtues. One of the virtues on the capitals, under the reliefs. It's resilience, strength. We see an allegorical figure representing this virtue - fortitude. This figure is very interesting, it reflects changes, opens a new trend. In fact, it no longer looks like a medieval sculpture. Exactly. Not too Romanesque. It's definitely not gothic. But what is it? Very strong influence of the ancient classics, in terms of appearance and meaning. Of course, a muscular athletic figure is a logical representation of stamina and strength. Further, one can guess who this figure represents: a lion skin is wound around his left arm, and he holds a lion cub on his right shoulder. This allows us to recognize in this naked, athletic, muscular figure of Hercules, or Hercules, a Greek and Roman mythological figure, a demigod known for his strength. At the same time, this is an antique character depicted in an antique style, and a symbol of Christian virtue. Correctly. This is the Christian virtue of strength and fortitude, embodied in the ancient hero Hercules. Accordingly, its meaning is ancient. Like you said, it looks antique. Marvelous. Perhaps the easiest way to see this is in comparison with real antique sculpture. Here we see a depiction of Fortitude by Niccolò Pisano in comparison with the "Diadumen" - an ancient sculpture, probably created by Polykleitos, its marble version. One can see in what Niccolo Pisano clearly imitated ancient sculpture that existed centuries before him. What elements did he copy, how did it influence his work? The resemblance is striking. They both stand in contraposta. Yes. They look very relaxed and natural in their poses. A lot of attention is paid to human anatomy, the muscles of the body, a kind of naturalism of the body. Yes. The body is somewhat twisted, looking in different directions. The hips are turned. Shoulders are turned. There is naturalism in this attention to the muscles, to the position of the body. And note: the sculpture of Niccolo Pisano, although connected to the pulpit, in fact it exists separately. The feeling that he can step off the pulpit. Exactly. We see here an ancient-looking figure, and the theme is also characteristic of antiquity, because Hercules is really depicted here. This is very important, because throughout the Middle Ages, up to this very moment, one can sometimes find figures in which the influence of antiquity is sometimes guessed. But usually they are very different in meaning from any ancient meaning. This is one of the first examples in this period of some kind of reunification of ancient form with ancient meaning, although it is ultimately a depiction of Christian virtue on a very Christian object inside an extremely Christian building. Here we see a growing interest, a kind of influence and the rediscovery of ancient classics in different forms. Right. In confirmation, let's compare some Gothic sculpture with antique. Here are examples of sculptural Gothic. From the western entrance to Chartres Cathedral, which was founded in the middle of the 12th century, about the same time that the baptistery in Pisa was being built, when these sculptures were created; a little before the creation of the pulpit by Niccolò Pisano. And far from here, in Paris. Yes, far away. We will show different schools of sculpture that existed at about the same time. You may know that Gothic is characterized by very static, elongated, stylized figures, deliberately far from any naturalism, with repeated folds of fabrics, with faces without personality, with the same gestures. These are figures that do not exist separately from the background. Their proportions and appearance dictated by the gothic construction they adorn. Look at their feet. They just can't stand. It's not like they're standing on anything, that they're interacting with the world around them with any degree of authenticity. Not a counterpost. Not a counterpost. Compared to the figure of Niccolo Pisano, this is a different era. It can be seen how decisively he departs from a similar Gothic tradition and from other traditions of the medieval Romanesque style. Let's look at the top of the pulpit, we can see our friend. Resilience right here. These reliefs, as we said, represent scenes or moments of the life and death of Christ. For example, in this scene, above and to the right of Fortitude, the Gifts of the Magi are shown, three kings who came to bow to the newborn Christ and the Virgin Mary, here she is sitting in an armchair. Here we see an ancient aesthetic, a departure from the Romanesque and Gothic styles, which are also visible in these reliefs. Undoubtedly. Monumental, heavy figures... Large folds of fabrics. Very heavy, somewhat naturalistic folds of fabrics that create ... Differ from the lines of draperies in Gothic. There are some repetitions. There is also some styling. But you can see that this is definitely a departure from these styles under the strong influence of the ancient classics. This is not surprising for the Pisans who used this object, saw it when it was first created. Why? Because this city has a very rich ancient heritage. Pisa was founded by the ancient Romans. The medieval Pisans knew this. The legacy of this ancient classic surrounded them everywhere you looked. They were surrounded by many examples of ancient sculpture. One example is the sarcophagus, a carved coffin that was then and still is in Pisa. There were a lot of such fragments and objects, some of them were even included in the medieval walls and buildings of the city, and the feeling that the ancient classics create the texture and character of Pisa was very clear. But she was hardly noticed. for a long time and now reopened. Now they felt that they could reconnect with this ancient heritage and history. This particular sarcophagus, especially in connection with the reliefs we have just looked at, is important because the figures here are quite large. They occupy the walls of the sarcophagus to the full height, just like the later reliefs of Niccolò Pisano. This nude standing athlete is very, very similar to the Fortitude figure, so this figure may have influenced the creation of that one. We see a seated woman who, although seated, occupies the entire height of the relief, just like the Virgin Mary in the Gift of the Magi we have just looked at. Maybe it was this example that Niccolo Pisano was guided by. It is very close - in the Camposanto cemetery, just a few meters from the Baptistery. Here we see the real influence of antiquity. The surname Niccolo Pisano means "Pisan", but he is not actually from Pisa. He is probably from the south of Italy, maybe connected with the court of the Emperor of the Holy Roman Empire, Frederick the Second, who was interested in antiquity and patronized its revival. Perhaps the artist, under the influence of this fact of his biography, comes to Pisa, sees a city with a rich ancient heritage, people open to such connections of times, and new forms flourish on this soil. Logically. Niccolo had a son, his name was Giovanni. They worked together on a number of projects. Around 1300, Giovanni Pisano opens his own workshop and works on his projects. Here is one of them. This is a pulpit from the church of Sant'Andrea in Pistoia, created in 1301. Its author is Giovanni Pisano. Essentially the structure is the same. There are colored marble columns with capitals, allegorical figures on the capitals under the reliefs that form the low walls of the pulpit. One difference immediately catches the eye: in the corners between the reliefs, instead of small columns, there are figures. This creates a sense of greater unity and connection between the individual reliefs, here they are not separated so clearly by these frames, as we saw in the work of his father, forty years earlier. There we saw columns in these places. I want to draw attention to one detail of this pulpit: the relief that we see at the top - "Massacre of the Innocents". Here is an episode from the New Testament, when Herod ordered to kill all the newborn boys in Bethlehem, after he learned about the birth of Christ. What is it new person, which will bring great changes that Herod does not need and he orders to commit this murder. And here we see this very emotionally heavy scene where the Roman soldiers kill the children. And mothers. Their mothers, as we see here, try to protect them or mourn their dead bodies. Or avert their eyes. They avert their eyes and run away. Soldiers with knives in their hands, cutting babies. Women covering their faces. Here Herod gives the order. In some respects, Giovanni Pisano's sculptures continue the work of his father. There is this naturalism, the origin of which we saw earlier. There is classicism, especially in some other elements of the pulpit. But what more clearly distinguishes the sculptures of Giovanni Pisano from the beginning of the 14th century is, of course, the growing interest in the transmission of emotions. This is a lively, somewhat expressionistic depiction of the feelings that this terrible scene that we are looking at evokes. She captivates the viewer. Through their gestures, their facial expressions. Exactly. This is the main tool for him and other artists of the period: the use of gestures and facial expressions to tell a story in the most expressive way. Of course, this is another sign of a departure from the Middle Ages, from those expressionless gothic faces. Especially in terms of combining such expressions, such emotions with naturalism. Because in Gothic art you can sometimes find something very scary and furious, but at the same time very stylized. Here we see a kind of naturalistic image, that is, naturalistic from the standpoint of physical form, from the point of view of psychological expressiveness. Interestingly, this happens in the early years of the 14th century, at the same time that Giotto does exactly the same thing in his paintings. Subtitles by the Amara.org community
Biography
Giovanni Pisano was born in Pisa around 1245. In 1265-78. Giovanni worked with his father, and with his participation, a pulpit was created for the city cathedral in Siena, as well as the Fonte Maggiore fountain in Perugia. The first independent work of Pisano is a sculptural decoration of the facade of the Pisa Baptistery (1278-84). For the first time in Tuscany, monumental sculpture was organically incorporated into architectural design. The extraordinary liveliness of the Pisan sculptures is the opposite of the calm serenity of his father's sculptures. Around 1270-1276 Pisano visited France. In most of his works, the influence of French Gothic is noticeable.
In 1285, Giovanni arrived in Siena, where from 1287 to 1296. served as chief architect of the cathedral. Full dynamics and drama figures sculptural composition The facades of the cathedral testify to the significant influence of French Gothic plastics on Pisano. Of all the Gothic Italian facades, the Siena Cathedral has the most luxurious sculptural decoration. Later, he served as a model for the decoration of the Gothic cathedrals of Central Italy. In 1299, Giovanni returned to Pisa, where he worked as an architect and sculptor in the construction of church buildings.
One of the greatest achievements of Giovanni Pisano is the pulpit for the church of Sant'Andrea in Pistoia (1297-1301). The theme of the reliefs decorating the pulpit is also similar to that of Pisa. However, the faces of the characters are more expressive, their postures and gestures are more dramatic. The scenes "Crucifixion" and "Massacre of the Innocents" are especially expressive. Giovanni Pisano is the author of numerous statues of Madonnas, prophets and saints. The most famous sculpture of the Madonna is in the altar of the Scrovegni Chapel (chapel del Arena) in Padua (c. 1305).
From 1302 to 1320 Giovanni Pisano worked on a pulpit destined for the Pisa Cathedral. After a fire in 1599, the pulpit was dismantled (during repairs) and restored only in 1926. The remaining “extra” fragments are kept in several museums around the world. In 1313, Giovanni began work on the gravestone of Empress Margaret of Luxembourg in Genoa (not finished). The last mention of Giovanni Pisano dates back to 1314, it is believed that he died shortly thereafter.
The article will focus on the life and work of the Italian sculptor and architect Niccolò Pisano. He is recognized as the founder of the Italian school of architecture, which influenced the artistic development of all of Italy.
Origin
Niccolo Pisano is considered to be the founder of the school of Italian sculpture and is the father of the famous talented sculptor Giovanni Pisano. He is also recognized as the founder of the Proto-Renaissance culture. The exact date of birth of the master is unknown. Researchers of his work say that 1219 can be considered the most probable date.
The sculptor was born in the city of Apulia, in southern Italy. If you turn to the Sienese archives, you will find that he is called the son of Pietro. "Pisano" is not a real surname, but only a nickname that the architect received after working in Pisa for a long time.
Studies
Niccolo Pisano, whose work demonstrates a clearly high level of skill, studied with ordinary masters in hometown. There is also an assumption that he studied in the workshops that worked from the marriage shoulder of Emperor Frederick II and were the focus of the classical tradition. It should be said that he arrived in Pisa already a fairly well-formed sculptor. As time has shown, he made the right decision, abandoning the Byzantine tradition for the sake of returning to the plasticity of the ancient world. It is believed that around 1245 Niccolò Pisano left for Tuscany, where he worked at the Castello del Imperatore in Prato.
After some time, the sculptor again changes his place of residence: he masters Lucca, where he continues to sculpt. A little later, he moved to Pisa (between 1245 and 1250). It was in this city that Niccolò Pisano met his future wife and became a father. Nothing is known about his beloved. Pisano loved his son very much and taught his skills with early years. Since moving to Pisa, he begins to appear in all documents under the name Niccolo Pisano.
Creation
Researchers cannot say exactly which works belonged to the hand of the sculptor Pisano. It is believed that it was he who was engaged in decorating the castle in Castello del Imperatore. It is most likely that he is also the author of the lions depicted on the portal of the castle. His work of the Tuscan period includes the "Head of a Girl", which is shown in Rome (Palazzo Venezia). In Lucca, he is engaged in decorating the facade of the Cathedral of St. Martin.
First masterpiece
Niccolo Pisano, whose sculptures were already found throughout Italy, in 1255 receives a specific order in Pisa, according to which he was to create a baptistery pulpit. The sculptor worked on this project with his friends Lapo di Richevuto and Arnolfo di Cambio. It was the first work that Pisano signed. It is considered his first masterpiece, since the master managed to combine the classics and the late Roman style.
It is believed that prior to this, Pisano actively studied the sculptural art of the times of Augustus, so much of it was reflected in the baptistery department. It was a 6-sided building made of white, pink and dark green marble, which rests on arches. The latter were made in the Gothic style in the form of a shamrock. The arches were supported by tall columns. At the corners of each arch there was a figure of one of the 4 main virtues (the most popular figure is the image of the Force in the form of Hercules). It is believed that the masters were inspired to create just such a baptistery by the triumphal arches of Rome, which he admired when he traveled to Ostia.
Let's remember that it is also decorated with columns and reliefs. The latter depict various scenes from the life of Jesus Christ: the Last Judgment, the Adoration of the Magi, the Bringing to the Temple, the Crucifixion, etc. Also, in the work on the baptistery, one cannot fail to notice the obvious classical influences that Pisano studied during court of Emperor Frederick II. It is believed that the best creations of Niccolo are the relief "Annunciation", "Adoration of the Shepherds" and "Nativity of Christ". In his work, the sculptor successfully combined the technologies of ancient masters and the modern sacred meaning of Christian customs. At the same time, the images of saints also resemble the works of ancient masters: they are majestic, sublime and restrained.
Completion of work with the son
Around 1264, Pisano was finishing work on the dome of the baptistery. Initially, the architect Diotisalvi was engaged in it, but then the work was given to Niccolò. The sculptor decided to make the baptistery taller and decorate it with two domes. Around 1278, Niccolo's son Giovanni came to the rescue and helped complete the baptistery by decorating the façade with sculptures. A little later, Niccolo began to work on the design of the reliquary for the relics of St. Dominic. Pisano's design was approved, but further work was denied. A little later, he nevertheless had a hand in creating a tomb for St. Dominica in Bologna with Fra Guglielmo.
Pulpit for Siena Cathedral
Around 1265, he begins to work on a pulpit for the Siena Cathedral. In total, he spent about three years on it. The pulpit was very similar to his first masterpiece - the baptistery. However, here he changed the scale and made the structure large in size. The decoration should also be noted, because it was much more luxurious than in the first work. He worked on the project with his true friends - the son of Giovanni, Arnolfo di Cambio and Lapo di Richevuto. If we analyze the voluminous figured bas-reliefs, we can say that the influence of French Gothic is very noticeable in them.
The last work of Niccolo and Giovanni Pisano is a fountain that was intended to decorate the main square in Perugia. Written evidence claims that Niccolò built the church of Santa Trinita in Florence as a reminder of the Cistercian Gothic that continued to develop in Italy.
Summing up, we can say that Niccolo became the forefather of the Italian school of sculpture, which lasted until the 14th century, and its influence spread throughout Italy. Much of Pisano's work belongs to the past: obsolete symbols and images remained, the space was filled completely, leaving no room for fantasy. But the works of Niccolò Pisano (his paintings) prepared society for great changes in the field of sculpture and architecture. They have become a kind of springboard for a high jump. The years 1260-1270 were very busy for the master, as he received orders from all over Italy.
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Separating this type of uranium from the more common variety requires great engineering skill, even though the technology needed to do so is decades old. The challenge is not to figure out how to separate the uranium, but to build and operate the equipment needed to accomplish the task.
Uranium atoms, like atoms of the elements found in nature in varieties, are called isotopes. (Each isotope has a different amount in its core.) Uranium-235, an isotope that makes up less than 1 percent of all natural uranium, provides fuel for nuclear reactors and nuclear bombs, while uranium-238, an isotope that makes up 99 percent of natural uranium, has no nuclear use.
Key to separation
The key to separating them is that uranium-235 atoms weigh slightly less than uranium-238 atoms.
In order to isolate the tiny amount of uranium-235 found in every natural uranium ore, engineers first convert the uranium into a gas through a chemical reaction.
The gas is then injected into centrifuge tubes in cylindrical shapes the size of a person or larger. Each tube rotates on its own axis at an incredible high speeds, pulling the heavier uranium-238 gas molecules into the center of the tube, leaving the lighter uranium-235 gas molecules closer to the edges of the tube, where they can be sucked out.
Each time the gas is spun in a centrifuge, only a small amount of uranium-238 gas is removed from the mixture, which is why the pipes are used in series. Each centrifuge pulls out some uranium-238 and then passes the slightly purified gas mixture to the next pipe, and so on.
Transformation of gas uranium
After separating the gaseous uranium-235 in many stages of centrifuges, engineers use a different chemical reaction to convert the gaseous uranium back into solid metal. This metal can later be shaped for use in either reactors or bombs.
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And designing and manufacturing these centrifuge tubes requires a certain level of investment and technical know-how beyond the reach of many countries. Pipes require special types of steel or mixtures that withstand significant rotational pressure, must be perfectly cylindrical and are made by specialized machines that are difficult to construct.
Here is an example of the bomb that the United States dropped on Hiroshima. It takes 62 kg of uranium-235 to make a bomb, according to "making the atomic bomb" (Simon and Schuster, 1995).
The separation of those 62 kg from nearly 4 tons of uranium ore took place in the world's largest building and used 10 percent of the entire country's electricity. It took 20,000 people to build the facility, 12,000 people operated the facility, and it cost more than $500 million to equip in 1944." That's about $7.2 billion in 2018.
