History of Ceramics

I'm so glad you've joined me on Lights Out Library tonight. If you'd like to listen ad-free and unlock bonus episodes, then please consider joining our Patreon. There is a link for it in the episode description. Now, a quick word from our sponsors before tonight's story begins. Hello, everyone. I'm Olympia. Thank you for being here with me in this wonderful place called Lights Out Library. And I have a great story to tell you. Tonight we're going to follow the long journey of one of humanity's oldest inventions, ceramics. Born more than 25,000 years ago, pottery has been shaping our daily lives ever since. It may sound ancient, even ordinary, but ceramics are anything but obsolete. From the plates on our tables and the tiles beneath our feet, to the bricks that build our cities, ceramics are everywhere. And even as you listen to this story, ceramics are at work inside, the very device you're using, hidden in the technology of modern electronics. So how do we create and reproduce all these objects? It all begins with the first one, the original, which is sculpted and polished by hand with clay. And once it is ready, its shape, its print, is taken in plaster. The matrix is made with plaster. It is like a negative version of the item. The matrix serves as a model for mold casts that will be used to make many more. Typically, these molds can be opened with a small opening at the top through which the clay is poured. The material used must be liquid enough to flow into every detail of the mold, so the clay is mixed with water until it reaches a consistency similar to melted chocolate or heavy cream. Over the course of a few hours, the raw material begins to set. The water does not simply evaporate through the small opening. Instead, it is mostly absorbed by the plaster of the mold. When the mold is opened, the piece has taken shape, but it is still very soft and fragile. It then needs to be left to dry for several days. Flat objects, such as plates or ashtrays, can be molded in a single piece. but for hollow containers like vases the form is usually made in two parts which are then carefully assembled while the clay is still wet and pliable. Now these plaster molds can be used a few dozen times only and they need to be remade regularly because they get damaged a little bit every time they serve. especially for pieces with more intricate detail they absorb water each time and have to dry between uses and because they are made of plaster they dissolve a little bit before pieces are fully dry there may be bits that need to be removed and a few days later when they are almost ready they are polished to look impeccable before the next step which is going to be painting applying a glaze the glaze or the coating of the ceramic has to be applied evenly on the pieces and this is obviously not regular paint we'll talk about the coatings of ceramic why they are very useful and also the art that appeared around it long ago once the glaze has been applied the time for transformation has come the miracle of firing items are placed in large ovens they're called kilns one can accommodate dozens of pieces in them depending on their size they are now mostly commonly electric and the temperature inside rises in excess of one thousand degrees c for several hours for comparison a kitchen oven can heat up to about three hundred degrees c maybe a bit more but this is three times more and the temperature reached inside these kilns would make many metals melt lead for example melts at just three hundred and thirty degrees zinc at four hundred and twenty so this is seriously hot The firing is essentially about transforming the piece. Thanks to chemical reactions, they become stronger, waterproof thanks to their coating, and the layer of paint also turns shiny. The pieces are then ready with their new properties, including a remarkable stability. organic matter like wood may decay metals can rust but ceramics stay exactly the same they are somewhat fragile but otherwise they will look like new in centuries the process has been perfected over several millennia there are variants to it There are also different types of ceramics that we will talk about, but these bases were laid long before metallurgy appeared. They spread or were invented in multiple places around the world, and this is exactly the long story we are going to explore tonight. But before we begin, a quick note. 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We have added links to Patreon in the description of the episode. and now let's take a moment to forget about our worries if you wish to you may close your eyes and immerse yourself in the story assume a comfortable position maybe move a bit to settle take a long deep relaxing breath and when you slowly exhale feel your shoulders drop release the tension in your neck let your face soften and your jaw relax make sure your fingers are not clenched and that your legs are relaxed too and allow the sound of my voice to guide you through this journey and now it's time to explore so how did it all begin the oldest known ceramic artifacts are almost thirty thousand years old long before the first sedentary communities living on agriculture appeared this corresponds to the late paleolithic and it is contemporary to the painting the ornamentation of a lot of prehistoric caves this tells us that ceramics were used before there were permanent villages with craftsmen practising metallurgy or more advanced forms of pottery with a wheel the discovery that clay and other materials could be fired and transformed to become harder and acquire new properties is one of the first innovations of mankind i'll tell you later about the various materials and the chemical reactions that happened during firing the very first ceramic objects we know of were not plates jars or everyday containers they were small figurines shaped by hand and fired at several hundred degrees probably in simple ovens rudimentary kilns dug into the ground some of the oldest known examples were discovered in central europe most famously a small female statuette known as the venus of bestonice found at a prehistoric settlement in what is now the czech republic these early figurines may have carried religious or symbolic meaning or perhaps they served as lucky charms The people of the region also produced hundreds of small animal figures, depicting the great creatures of the Ice Age, by humans living in a world shaped by glaciers, harsh climates, and the great animals of the Pleistocene. Reproducing the image of these animals was likely charged with meaning. an act that mattered deeply to these communities. These objects were probably not simple toys or mere decoration, but part of a symbolic world in which early humans tried to understand, represent, and perhaps even influence the forces around them. The oldest ceramic objects we currently know of come from Central Europe, largely because exceptionally well-preserved prehistoric sites were discovered there but it is very likely that the earliest experiments with clay and fire did not happen in just one place similar discoveries may have occurred independently in different parts of the world or spread between communities because twenty to thirty thousand years ago humans already had mastery over fire and clay was abundant around many settlements the knowledge that earth could be shaped and transformed by heat may have emerged more than once wherever people had the materials the curiosity and the time to experiment may be prehistoric man just observed that earth or sand round and under their fires seemed to change appearance and texture after having been heated for a while and they had the idea of trying this intentionally. We do not know exactly, but between these first figurines and the first examples of actual pottery, many generations passed, at least 10,000 years based on archaeological discoveries. But what is the difference between ceramic pottery, terracotta, earthenware, and other terms like porcelain. It depends on the context. Technically, pottery is an object, often a vessel, but it can be a decorative object too, formed with ceramic material and fired at high temperatures to make it harder and more durable. So in that sense, earthenware or porcelain are part of pottery and they are also ceramic, which is a broad term that refers to any mineral material that has been fired to modify its properties. So a brick or a floor tile, for example, is technically a ceramic, but it isn't usually described as pottery. Pottery refers to ceramic objects that exist as items in their own right, vessels, bowls, cups, figurines, things made to be used, held, or displayed. bricks and tiles by contrast are ceramics designed as building materials meant to become part of a larger structure rather than stand alone as individual objects Now that would be a general definition of pottery because when it comes to archaeology pottery in this context only means vessels and this is how we understand pottery as long as it is about remains found on prehistoric or antique sites in the same context figurines are more often called terra which literally means baked earth it's the same material same firing process this is just a distinction based on destination that archaeologists make and then another important distinction is between earthenware stoneware or porcelain which are different types of clay based pottery porcelain is a type of ceramic that was invented in china long after the two others we'll come back to this extensively later and it had revolutionary properties at the time porcelain is like the most advanced in technical material when it comes to pottery vessels it requires very specific clay material and a high firing temperature before it there was earthenware and stoneware earthenware was probably the oldest type of pottery it is fired below twelve hundred degrees c that's twenty four hundred fahrenheit it is also sometimes called terra cotta and it is non vitreous meaning that it absorbs liquids such as water It is still very present in our homes, except it generally doesn't absorb water because it is coated with a ceramic glaze. The pieces made are waterproof, but not thanks to the ceramic material itself. It is thanks to the coating that is applied to it before firing. then stoneware appeared which is a broad category for pottery fired at higher temperatures and with a more specific formula the main difference with earthenware is that due to the higher temperatures and the different material stoneware is non-porous and it is often vitrified that is to say turned into a sort of glass this basically means that contrary to earthenware it does not absorb liquids this was an interesting property that made stoneware successful for utilitarian wares and higher quality products and here again China was a precursor The first stoneware artifacts appeared either in India, in the Indus Valley, or in China. But in China, and also in Japan, they became rather abundant. Stoneware began to be produced in Europe much later, during the Middle Ages. and then came porcelain another Chinese invention that the Europeans were eager to imitate until they broke the code and found the formula in the 18th century so that was just a quick tangent about definitions now let's go back to history so as I mentioned the first examples of pottery in the sense of vessels appeared about 20,000 years ago and the earliest fragments were found in China. It is believed that from China the use of pottery spread to Japan and the Russian Far East. Because shards of ceramic artifacts were found in these regions and they date from the following millennia, did it then spread to the rest of the world or was it invented in multiple places we don't know exactly but during the neolithic the making of pottery vessels was present on all continents there are traces in europe and in africa south of the sahara in the tenth millennium b c and slightly later in america everywhere around the world pottery became relatively common ten thousand years ago it was cheap to produce at least in comparison with precious artifacts and it is probably the first types of wares that were made in larger facilities we are not talking about industrialization yet but as early as antiquity there were production centers that rationalized its production divided tasks and produced vessels not only for local consumption but for an entire region or sometimes for trade this appeared in china in india in mesopotamia in egypt and south america and it is quite unique because it seems the same didn't happen on such a scale for other products like textiles for example For thousands of years, objects were formed either manually or maybe using molds, until the wheel was invented. It is believed that the wheel was invented first in Mesopotamia, and together with the first wheeled vehicles, the first potter's wheels appeared somewhere in Mesopotamia in the 5th millennium B.C., and this helped to create curved pottery that was smoother more regular and probably much faster to produce which made potters more productive another important aspect is that pottery was decorated very early on ceramic vessels became supports for decoration and artistic expression carrying patterns symbols and sometimes stories that went far beyond their practical use this brings a wealth of information about antique civilizations fragments of pottery can be dated using carbon dating which helps a lot to know not only when they were made but what period an entire layer or an archaeological site belonged to their decoration also tells us of the tools that were used the styles the techniques they reveal a lot more than the fragments themselves and pottery was also traded so it tells us of the connections between cultures that could sometimes live thousands of miles apart for example an early people that spread across much of europe is named after its use of pottery the corded ware culture they are called corded ware culture because they had a specific way of decorating their pottery they wrapped it with rope while it was still wet so this left a decorative pattern and then they fired their pottery the rope burned off and the patterns imprinted the ceramic the corded ware culture spread across europe about five thousand years ago in the late neolithic and it ended in the early bronze age several centuries later but the extent of its presence and the period could entirely be mapped thanks to the dating and specific aspects of their pottery the use of pottery vessels spread widely during the neolithic period and so did architectural ceramics tiles and even more so bricks especially in regions where wood was scarce for construction such as egypt bricks were widely used for buildings stone was too expensive and slow to use for building so it was reserved for tombs like pyramids or for temples which are the egyptian monuments that have crossed the centuries but ancient egypt was essentially built with bricks often just right in the sun so in that sense they were not really ceramics until they realized that bricks could become much harder and durable if fired in a kiln so what is a kiln exactly it is a term for a type of oven a chamber that is thermally insulated it can concentrate heat and can be used for the firing of ceramics because it reaches these temperatures that are much higher than the one the basic oven for cooking could ever reach the ancient version at least at the start was quite rudimentary they basically just were holes dug in the ground but across the centuries kilns were perfected and they became more and more efficient reaching peaks of temperature in ancient china and to a lesser extent in greece and the roman empire so speaking of this let's take a look at the art of pottery in various ancient civilizations starting with egypt cause it's always interesting to speak about ancient egypt we know about how egyptians made pottery mainly from depictions on the walls of tombs and temples along the many centuries of egyptian history more techniques to form vessels and other objects appeared but they all remained in use until the end at first ceramic objects were shaped entirely by hand but hand building had its limits the walls of these early vessels tended to be quite thick and it was difficult to make large pieces from wet clay before firing the material is heavy and fragile and taller or wider forms can collapse under their own weight over time these practical limits pushed potters to invent new techniques new ways of shaping clay that made lighter larger and more regular forms possible one that was used for large items such as tubs was to make flat and relatively thin rectangular pieces of wet clay and then weave them together before firing this is recognizable on archaeological sites because when broken these items tend to form rectangular shards they broke where they were the weakest the potter's wheel was introduced in the third millennium b c either copied from mesopotamia or re-invented locally the first potter's wheels were slow the potter would make them turn with one hand and form objects with the other hand as i mentioned before it not only facilitated the making of symmetrical and almost perfectly curved objects but it was also much faster and pottery could be somewhat standardized thanks to them so like in other cultures it came with a kind of mass production egyptians also used moulds especially to make the breadpans in which small conical breads were baked these moulds were probably just a cone of wood shaped like these breads and they added clay around it before letting it dry and then firing the pottery later in the second millennium b c during the new kingdom the last period of egyptian unity and independence in antiquity before the country was invaded multiple times so during the new kingdom faster potter wheels were introduced they were no longer put in motion by hand but by the potter's feet this made the forming of vessels even more productive so in egypt pottery was widespread and part of everyone's life even poor people had cups bowls and plates and often figurines of small animals and gods before the clay had fully dried simple decoration was often added even on inexpensive everyday pieces a few incised lines small impressions made with stamps or basic patterns were enough to give each object a distinct identity the piece was then left to dry thoroughly before it could be fired like others the egyptians had discovered that the pieces needed to lose almost all their water before firing because if they didn't water did not just evaporate in the kiln Some of it stayed trapped inside the walls of the items, so it boiled, and it could even make the piece explode. So they always needed to be already dry before firing. The Egyptians had figured out that they could change the aspect of their pottery during firing too They realized that if they allowed a good supply of air enter the kiln the resulting pottery could take a red to brown color. It is because there is iron in clay, so when oxygen is abundant during firing, they tend to combine and form iron 3 oxide, also known as rust. Whereas when they rationed air and oxygen, pottery took a gray to black color, because with less oxygen available, iron 2 oxide formed instead. They didn't know how that worked chemically, but they used this process to vary their decoration and their colors. And they also discovered more and more oxides that were introduced for more colors, blue, yellow, white. there were fashions in the decorative patterns not really fashions in the modern sense because they typically lasted for several generations not years like nowadays but most Egyptian pottery especially luxury pieces can be approximately dated by experts just by looking at the patterns heads of gods like the goddess Hathor or Bess a god that protected houses lotus flowers, papyrus, grapes some of the pieces were found intact in tombs after thousands of years and they are a testimony of the refinement that the Egyptians were capable of they are exquisite and require the sum of different materials and know-how that could only be accumulated after centuries of trial and error. We know that the pottery in Egypt had turned to an industrial activity in the sense that there were large workshops and in various sites the remains of multiple kilns were found. This indicates that production went on constantly and most of it was to be sold. The status and the economic importance of pottery is less known. There is another civilization in which pottery had a major importance economically and it is ancient Greece. There is an international research project about ancient ceramics that lists all known items. it is called the corpus basurum antiquorum the corpus of ancient vases yes it's a thing it contains records of over a hundred thousand greek painted vases and when you think that most of the pottery produced in greece was probably lost it gives you an idea of the millions and millions of pieces of greek pottery that were made the greeks produced everyday pottery for kitchen use of course but they also developed a production of fine pottery of luxury goods that they exported all around the mediterranean sea not all of it was produced in greece greek colonies also participated such as in the south of italy the greeks invented or used shapes that we associate with their culture for example the amphora it is a type of container with a pointed bottom and they could fit tightly against each other which made them perfect for transport by boat this reduced the risk of losing cargo because once they were positioned inside the ship and tied together with rope they wouldn't move they were used in vast numbers to transport not just liquid like wine but dry products too and most of them were ceramics even though there are a few examples of amphoras made of metal at the same time pottery was much cheaper and accessible than copper bronze or later iron of course another greek container was the pithos a large storage container that was used for bulk storage this one could stand on its own on its base more than other cultures they also made vessels with a specific purpose for example for mixing the crater the large vase made to mix water and wine the practice of drinking pure wine was very uncommon in antiquity it was almost always diluted with water the greeks had different kinds of cups depending on the liquid they would receive the most common type of wine-drinking cup is called a kylex a kylex had a broad body raised on a stem from a foot and usually there were two handles on either side an alternative was the cantharus which was narrower and higher with vertical handles they also had more types of vases for oils for cosmetics and perfumes they made vases designed to serve as grave markers and these are just a few examples of the extraordinary variety of greek pottery what greek pottery is also famous for is the ambitious figurative painting on it in the first centuries when greek culture emerged the decoration of pottery was dominated by geometric patterns and a lot of circular and wavy patterns too there were a few figurative elements probably inspired by crete where the minoan civilization was flourishing at the time but not that many the practice to depict characters and scenes on pottery really took off and dominated from the seventh to the third centuries b c and the production of vases was dominated at the time by athens you know that ancient greece was not a single state at least not until it was unified later by alexander the great It was a cultural area with a collection of small states, and the city-state of Athens was one of the most important. Athens invented the so-called red figure technique, that is to say a black background with characters painted in shades of yellow to red. Before, characters were typically painted in black on a red background. and in production centers, vases and other vessels became a support of choice for artistic expression. In a sense, similar to painting on a canvas in modern painting. And the Greeks also developed a white ground technique later, by the end of the 6th century BC. Black figures and red figures were obtained through the application and firing of thin layers of slips. Slips are mixtures of minerals diluted in water. These colors were not applied on vases after firing. They were part of the vase itself. The white ground technique involved Greek potters first coating the surface of a vase with a fine white slip, a liquid clay that dries pale. Artists then drew figures on this white surface, usually an outline, and added color with mineral pigments. And it was a valuable innovation because it allowed for more colors on vases. It is this mix of technical innovations and artistic value that made the Greeks dominate this trade in the Mediterranean. Their clients also knew pottery, of course, and produced their own vessels, but they just couldn't do what the Greeks were able to do in terms of technical achievement and style. And production in Athens or other cities was a true industry, perhaps the first example of an industry for consumer goods because their production of other goods like textiles or furniture was much more decentralized whereas pottery was mass-produced to meet strong demand for elaborate luxury goods or for transport of food and beverages all around the Mediterranean Sea. as the egyptians and later the greeks were developing their pottery so were pre-columbian cultures in america and this was also remarkable the earliest known ceramics from the americas were found in brazil in the north near the city of santarem on the amazon river and they have been dated between eight thousand and seven thousand years ago they were produced by a culture of fishermen and shellfish gatherers that is otherwise little known between seven thousand and five thousand years ago ceramics appeared all across north central and south america it is unclear whether the migrations that came from asia brought ceramic or if it was reinvented locally in the americas maybe both happened but in any case pottery was present several thousand years ago from the arctic region the south of the continent these cultures were often in contact with each other but their geographical knowledge was limited to their region and its surroundings so many different traditions formed and pottery could look very different in north america the mississippian culture that existed in the american midwest and southwest in the second and third millennium b c used to temper clay with ground shell tempering is the practice of mixing clay with other materials it could be ash charcoal sand bone or in this case shell the reason for tempering clay is that it avoids shrinkage or cracking during drying and firing of vessels pretty much every culture discovered this and they developed their particular formulas there were several other major ceramic traditions in what became the united states the ancestral puebloans from the southwest is another one and the shapes and decorative patterns are all very different but if we consider the americas as a whole an element that comes back more often than in any other parts of the world is the production of sculptures to make ceramic objects especially human heads or faces they all produced vessels and all the containers they needed but there was also a rich tradition of creating figurines sometimes quite large and decorating objects like urns musical instruments and even household pottery with sculpture ceramic was a form of artistic expression that still exists to-day of course but it has lost the kind of pre-eminence it used to have in these cultures when we think about fine arts to-day we are probably more inclined to think about painting or sculpture this is a reminder that the forms of art and expression are not set in stone it is well possible that in a few centuries people will be surprised that western artists of the sixteenth to the twenty-first centuries were so obsessed with painting on canvases let's go on because we still have more regions in the world to visit and before we talk about china let's make another stop in the medieval islamic world because it also developed an aesthetic that mixed influences from the mediterranean world and asia and more than any other cultural area they used ceramic to decorate buildings with tiles when the expansion of islam began in the seventh century they inherited various ancient pottery industries in mesopotamia in persia in egypt and north africa and with them centuries-old techniques and styles this knowledge circulated within the islamic world for several centuries and it was also in contact with china which was very influential because it was not just the most advanced part of the world when it came to ceramics we'll get to this in a minute the chinese had also created a variety of styles of shapes and colors that were very appealing to foreigners starting with all these influences and the circulation of techniques islamic potters soon developed their own innovations in the ninth century they started producing stoneware You remember the difference between earthenware and stoneware It is the earthenware is porous It is fired at lower temperatures and it needs to be coated to become waterproof, whereas stoneware is vitreous and non-porous, but harder to make because it requires mixing ingredients precisely and also higher firing temperatures. In Persia, lusterware was developed. These are a type of pottery with a metallic glaze that makes them iridescent. Another thing that the Islamic world would prove very good at developing was tin-glazed pottery. also known as Fiance which is earthenware covered in lead glaze with added tin oxide this gives it a white and shiny appearance Fiance was a huge success in Europe it was imitated in Spain and Italy in France and in Northern Europe it is still produced historically finance industries developed in several European cities an important one was Delft in the Netherlands which developed a distinctive white and blue style until the 18th century this was the best Europeans could do they knew of Chinese porcelain because pieces arrived brought by traders or as diplomatic gifts, and they couldn't help but notice that faience looked like the poor man's porcelain, because it is typically much thicker. Earthenware needs a minimal thickness to stay in one piece, and there is coating on both sides. So in comparison with porcelain vessels, it looks more rustic, and it can be very white and shiny, but it doesn't have the translucent properties of porcelain. I'll tell you more about that when we speak of China. Returning to the Muslim world, another tradition in Islamic art and architecture that is still very visible today in Muslim countries and that started in the 9th century was to decorate the inside and outside of buildings with brightly colored tiling, generally arranged in geometric patterns. This was probably inspired by Byzantine mosaics at the start. The first examples were made like mosaics with many small tiles of one color that were cut and arranged to create patterns. then later with a better knowledge of firing and oxides to obtain colors they started to make entire panels that were painted before firing which is a much faster way of covering surfaces the very intricate patterns on the domes and the walls typically geometric patterns or text or flowers or foliage are painted before firing, and once they are turned into ceramic, they provide at the same time ornamentation and protection because they are waterproof and very durable. Our tour would not be complete without a stop in China because since ceramic appeared, China has been the place where most innovations have taken place and its tradition is so rich and ancient that entire encyclopedias could be written about it. I mentioned at the beginning that the very first known potteries appeared in China almost 20,000 years ago during the Paleolithic era. The Chinese invented stoneware centuries before anyone else, as far as we know. They mastered the art of making porcelain nearly 2,000 years before Europeans, who only much later succeeded in producing true porcelain outside of China. The Chinese also used ceramic as building material for thousands of years. bricks and tiles and when it comes to production and trade they dominated the world market as soon as trade connections were established in antiquity they produced on an industrial scale that served everyone from the popular Chinese markets for kitchenware to a more discriminating Chinese market all along the centuries Wealthier people had a knowledge and interest in ceramics in China. It was a sought-after luxury or upscale type of good. It was collected and used as decoration centuries before the same trend began in Europe. And up to the court of emperors who had access to the finest porcelain. So what made China so advanced in this field? Probably a combination of interest in ceramics that made the Chinese invest a lot in experimenting techniques, the internal competition between artisans and dynasties, and the interest of emperors, and the taste of the elite for luxury goods. The same could probably said of silk, for example And thanks to all this, there were a few technological breakthroughs The Chinese made kilns that could reach higher temperatures Thanks to better insulation and ventilation Making stoneware and porcelain requires temperatures above 1200 degrees Celsius and these were reached in China in the first millennium BC, long before other parts of the world, as far as we know. And more than in other cultures, they worked on mixing clays with all sorts of ingredients. This is probably how porcelain was invented, as one of many experiments. The one key ingredient in it is kaolin, which is a clay mineral that comprises aluminum and silicon. This is quite specific, and there can be other ingredients necessary like quartz, and it must be fired at high temperature. temperature, and porcelain obtains its properties. The hardness translucens from a process of vitrification. Porcelain is not glass, though. Even though technically glass could be considered a kind of ceramic, it is a raw material. In the case of glass, a mix of sand, soda, and potash is transformed chemically by firing. But glass is generally not considered to be a type of ceramic because the ingredients are very different and the production process is also very different. Typically ceramics are formed and then they are fired, glasses heated first to obtain a hot paste, and only after that her objects form with the paste. Glass can also be melted again and transformed. It won't return to its original ingredients, but it can be recycled and made liquid again, not ceramics. They can only be broken. Technically, it would not be impossible to liquefy ceramics at extremely high temperatures and do something else with the paste obtained, but this is too complicated and not worth it. So contrary to glass, it is not recycled at all into new objects. The exact date when the fabrication process of porcelain was invented is unclear. Because there were intermediate stages in the elaboration of the formula, the first proto-porcelain that was vitrified hard and white appeared during the Han Dynasty in the first three centuries of her era I made a story about the Great Wall and the history of ancient China if you want to know more about the context you can find it in my library and by the 7th century AD the formula had been perfected and stabilized with production on an industrial scale. Horseland was a huge success early on, and demand was very strong. To give you an idea of the scale of this production, the Chinese had developed long kilns that could be up to 60 meters long, That's about 200 feet. They are called dragon kilns, and kilns had a fairly steep slope, hence the name probably, that they let hot air circulate inside. Up to 25,000 pieces could be fired at once inside these kilns. The industry spread to Japan, but the Chinese protected their fabrication secrets because they generated a considerable income and prestige from them. Chinese porcelain began to flow into Europe in the 6th century, brought by Portuguese and then Dutch traders, and a technology race between faience makers to try to imitate it, especially the white and blue design that remains associated with chinese porcelain because at the time under the ming dynasty it was popular there in china in the process various processes were invented that are not the real thing but still represented innovations and they are still produced to-day like bone china which was invented in england trying to replicate the chinese formula it contains bone ash which is what you get when you calcinate animal bones as the name says it contains calcium oxide and phosphorus and it looked better than the thick faience that was produced at the time but it didn't have the transparency and the hardness of real porcelain another example was soft paste porcelain it is called soft paste because it lacks hardness so it could be stretched rather easily and there were many formulas for it but they didn't come close to the chinese one because there was no kaolin finally at the beginning of the eighteenth century the code was cracked in meissen germany and later in other european countries and a european porcelain industry took off along the eighteenth century with success but still the chinese maintained a huge production and remained the maker of porcelain especially the city of chingdejen this is where the porcelain industry was concentrated at the time of the ming dynasty ceramic palaces and homes for decorative purposes probably reached its peak in the eighteenth and nineteenth centuries but it is still very present in everyday life i'm sure if you start paying attention to it in your home you will be surprised at how many items you own in your cupboards plates mugs bowls cups and possibly all around the house lamps vases and other decorative objects it is a different story but in the twentieth century industrial ceramics started to be used for their properties like hardness stability and resistance to high temperatures so they can be found in all sorts of devices and facilities from semiconductors to cooktops to nuclear plants we have reached the end of tonight's story there would be much more to say about ceramics but you know where to find documentaries or books and you can also pay a visit and support local artisans who keep this tradition alive the sum of technique know-how and talent that can be behind simple objects that we see every day can be impressive and by paying attention to this you train yourself to go beyond appearances and realize how rich and interesting our environment can be it is easy to see things without looking at them looking into them and in the process ignore all the depth and substance there enclosed so it can be ceramic and it can be other things but start looking at them more closely and ask yourself questions about these little things around you i hope you enjoyed this adventure now you can let go and sleep or if you're not sleepy yet you may pick another story from my ever-growing library and until we meet again good night sleep well Thank you.