Soapstone is a talc-schist, a type of metamorphic rock. It is composed of the mineral talc, thus is rich in magnesium, it is produced by dynamothermal metamorphism and metasomatism, which occur in the zones where tectonic plates are subducted, changing rocks by heat and pressure, with influx of fluids, but without melting. It has been a medium for carving for thousands of years. Petrologically, soapstone is composed dominantly of talc, with varying amounts of chlorite and amphiboles, trace to minor iron-chromium oxides, it may be massive. Soapstone is formed by the metamorphism of ultramafic protoliths and the metasomatism of siliceous dolostones. By mass, "pure" steatite is 63.37% silica, 31.88% magnesia, 4.74% water. It contains minor quantities of other oxides such as CaO or Al2O3. Pyrophyllite, a mineral similar to talc, is sometimes called soapstone in the generic sense, since its physical characteristics and industrial uses are similar, because it is commonly used as a carving material. However, this mineral does not have such a soapy feel as soapstone.
Soapstone is soft because of its high talc content, talc having a definitional value of 1 on the Mohs hardness scale. Softer grades may feel similar to soap the name. No fixed hardness is given for soapstone because the amount of talc it contains varies from as little as 30% for architectural grades such as those used on countertops, to as much as 80% for carving grades. Soapstone is used as an insulator for housing and electrical components, due to its durability and electrical characteristics and because it can be pressed into complex shapes before firing. Soapstone undergoes transformations when heated to temperatures of 1000–1200°C into enstatite and cristobalite. Ancient Egyptian Scarab signet/amulets were most made from glazed steatite. Soapstone is used for inlaid designs, sculpture and kitchen countertops and sinks; the Inuit used soapstone for traditional carvings. Some Native American tribes and bands make bowls, cooking slabs, other objects from soapstone. Locally quarried soapstone was used for gravemarkers in 19th century northeast Georgia, US, around Dahlonega, Cleveland, as simple field stone and "slot and tab" tombs.
Small blocks of soapstone were heated on the cookstove or near the fire and used to warm cold bedclothes or to keep hands and feet cozy while sleighing. Vikings hewed soapstone directly from the stone face, shaped it into cooking pots, sold these at home and abroad. Soapstone is sometimes used for construction of fireplace surrounds, cladding on wood-burning stoves, as the preferred material for woodburning masonry heaters because it can absorb and evenly radiate heat due to its high density and magnesite content, it is used for countertops and bathroom tiling because of the ease of working the material and its property as the "quiet stone". A weathered or aged appearance occurs over time as the patina is enhanced; the ancient trading city of Tepe Yahya in southeastern Iran was a center for the production and distribution of soapstone in the fifth to third millennia BC. It was used in Minoan Crete. At the Palace of Knossos, archaeological recovery has included a magnificent libation table made of steatite.
The Yoruba people of West Nigeria used soapstone for several statues, most notably at Esie, where archaeologists have uncovered hundreds of male and female statues about half of life size. The Yoruba of Ife produced a miniature soapstone obelisk with metal studs called superstitiously "the staff of Oranmiyan". Soapstone has been used in India for centuries as a medium for carving. Mining to meet worldwide demand for soapstone is threatening the habitat of India's tigers. In Brazil in Minas Gerais, due to the abundance of soapstone mines in that Brazilian state, local artisans still craft objects from that material, including pots and pans, wine glasses, jewel boxes and vases; these handicrafts are sold in street markets found in cities across the state. Some of the oldest towns, notably Congonhas and Ouro Preto, still have some of their streets paved with soapstone from colonial times; some Native Americans use soapstone for smoking pipes. Its low heat conduction allows for prolonged smoking without the pipe heating up uncomfortably.
Some wood-burning stoves make use of soapstone to take advantage of its useful thermal and fire-resistant properties. Soapstone is used to carve Chinese seals. Soapstone is most used for architectural applications, such as counter tops, floor tiles and interior surfacing; the active North American soapstone mines include one south of Quebec City with products marketed by Canadian Soapstone, the Treasure and Regal mines in Beaverhead County, Montana mined by the Barretts Minerals Company, another in Central Virginia operated by the Alberene Soapstone Company. Architectural soapstone is mined in Canada, Brazil and Finland and imported into the United States. Welders and fabricators use soapstone as a marker due to its resistance to heat, it has been used for many years by seamstresses and other craftsmen as a marking tool because its marks are visible and no
A lapidary is an artist or artisan who forms stone, minerals, or gemstones into decorative items such as cabochons, engraved gems, faceted designs. A lapidarist uses the lapidary techniques of cutting and polishing. Hardstone carving requires specialized carving techniques. Diamond cutters are not referred to as lapidaries, due to the specialized techniques which are required to work diamonds. In modern contexts a gemcutter is a person who specializes in cutting diamonds, but in older historical contexts it refers to artists producing engraved gems such as jade carvings. By extension, the term lapidary has sometimes been applied to collectors of and dealers in gems, or to anyone, knowledgeable in precious stones; the etymological roots of the word lapidary is the Latin word lapis. In the 14th century, the term evolved from lapidarius, meaning "stonecutter" or "working with stone", into the Old French word lapidaire, meaning "one skilled in working with precious stones". In French, English, the term is used for a treatise on precious stones that details their appearance and properties—particularly in terms of the "stones' powers"—as believed in medieval Europe.
The beliefs about the powers of stones included their ability to prevent harm, heal ailments, or offer health benefits. Lapidary appeared as an English adjective in the 18th century; the earliest known lapidary work occurred during the Stone Age. As people created tools from stone, they realized that some geological materials were harder than others; the next earliest documented examples of what one may consider to be lapidary arts came in the form of drilling stone and rock. The earliest roots of drilling rocks date back to one million years ago; the early Egyptians developed cutting and jewelry fashioning methods for lapis lazuli and amethyst. The lapidary arts were quite well-developed in the Indian subcontinent by early-1st millennium CE; the surviving manuscripts of the 3rd-century Buddhist text Rathanpariksha by Buddha Bhatta, several Hindu texts of mid-1st millennium CE such as Agni Purana and Agastimata, are Sanskrit treatises on lapidary arts. They discuss sources of gems and diamonds, their origins, testing and polishing, making jewelry from them.
Several other Sanskrit texts on gems and lapidary arts have been dated to post-10th century, suggesting a continuous lapidary practice. According to Jason Hawkes and Stephanie Wynne-Jones, archaeological evidence suggests that trade in lapidary products between Africa and India was established in the 1st millennium CE. People of the Deccan region of India and those near the coast of East Africa had innovated their own techniques for lapidary before the 10th century, as evidenced by excavations and Indian and non-Indian texts dated to that period. Lapidary was a significant tradition in early Mesoamerica; the lapidary products were used as status symbols, for offerings, during burials. They were made from shell, jade and greenstones. Aztec lapidaries used string drills made of reed and bone as their lapidary tools. There are three broad categories of lapidary arts: tumbling, cabochon cutting, faceting. Most modern lapidary work is done using motorized equipment. Polishing is done with resin- or metal-bonded emery, silicon carbide, aluminium oxide, or diamond dust in successively decreasing particle sizes until a polish is achieved.
In older systems, the grinding and polishing powders were applied separately to the grinding or buffing wheel. The final polish will use a different medium such as tin oxide or cerium oxide. Cutting of harder stones is done with a diamond-edged saw. For softer materials, a medium other than diamonds can be used, such as silicon carbide, emery, or corundum. Diamond cutting requires the use of diamond tools because of the extreme hardness of diamonds; the cutting and polishing operations are lubricated with water, oil, or other liquids. Beyond these broader categories, there are other specialized forms of lapidary techniques, such as casting, carving and mosaics. Another specialized form of lapidary work is the inlaying of marble and gemstones into a marble matrix; this technique is known in English as pietra dura, for the hardstones that are used, like onyx and carnelian. In Florence and Naples, where the technique was developed in the 16th century, it is called opere di commessi; the Medici Chapel at San Lorenzo in Florence is veneered with inlaid hard stones.
The specialty of micromosaics, which developed in the late-18th century in Naples and Rome, is sometimes covered under the umbrella term of lapidary work. In this technique, minute slivers of glass are assembled to create still life, cityscape views, other images. In China, lapidary work specializing in jade carving has been continuous since at least the Shang dynasty. There are lapidary clubs throughout the world. In Australia there are numerous gem shows, including an annual gem show called the GEMBOREE, a nationwide lapidary competition. There is a collection of gem and mineral shows held in Tucson, Arizona, at the beginning of February each year; the event began with the Tucson Gem and Mineral Society Show and has now grown to include dozens of other independent shows. In 2012, this concurrent group of shows constituted the largest mineral event in the world. Amber Diamond Gemstone Handicraft Jade Pearl Ruby
In the classification of Archaeological cultures of North America, the Woodland period of North American pre-Columbian cultures spanned a period from 1000 BCE to European contact in the eastern part of North America, with some archaeologists distinguishing the Mississippian period, from 1000 CE to European contact as a separate period. The term "Woodland Period" was introduced in the 1930s as a generic term for prehistoric sites falling between the Archaic hunter-gatherers and the agriculturalist Mississippian cultures; the Eastern Woodlands cultural region covers what is now eastern Canada south of the Subarctic region, the Eastern United States, along to the Gulf of Mexico. This period is variously considered a developmental stage, a time period, a suite of technological adaptations or "traits", a "family tree" of cultures related to earlier Archaic cultures, it can be characterized as a chronological and cultural manifestation without any massive changes in a short time but instead having a continuous development in stone and bone tools, leather crafting, textile manufacture and shelter construction.
Many Woodland peoples used spears and atlatls until the end of the period, when they were replaced by bows and arrows. The most cited technological distinction of this period was the widespread use of pottery, the diversification of pottery forms and manufacturing practices; the increasing use of horticulture and the development of the Eastern Agricultural Complex, consisting of weedy seed plants as well as gourd cultivation meant that groups became less mobile over time and, in some times and places, people lived in permanently occupied villages and cities. Intensive agriculture characterizes the Mississippian period from c. 1000–1400 CE and may have continued up to European contact, around 500 years ago. The Early Woodland period continued many trends begun during the Late and Terminal Archaic periods, including extensive mound-building, regional distinctive burial complexes, the trade of exotic goods across a large area of North America as part of interaction spheres, the reliance on both wild and domesticated plant foods, a mobile subsistence strategy in which small groups took advantage of seasonally available resources such as nuts, fish and wild plants.
Pottery, manufactured during the Archaic period in limited amounts, was now widespread across the Eastern Interior, the Southeast, the Northeast. The Adena culture built conical mounds in which single- or multiple-event burials cremated, were interred along with rich grave goods including copper bracelets and gorgets, art objects made from mica, hematite, banded slate, other kinds of stone, shell beads and cups, leaf-shaped "cache blades"; this culture is believed to have been core to the Meadowood Interaction Sphere, in which cultures in the Great Lakes region, the St. Lawrence region, the Far Northeast, the Atlantic region interacted; the large area of interaction is indicated by the presence of Adena-style mounds, the presence of exotic goods from other parts of the interaction spheres, the participation in the "Early Woodland Burial Complex" defined by William Ritchie Pottery was manufactured and sometimes traded in the Eastern Interior region. Clay for pottery was tempered with grit or limestone.
Pots were made in a conoidal or conical jars with rounded shoulders constricted necks, flaring rims. Pottery was most decorated with a variety of linear or paddle stamps that created "dentate" impressions, wavy line impressions, checked surfaces, or fabric-impressed surfaces, but some pots were incised with geometric patterns or, more with pictorial imagery such as faces. Pots were coiled and paddled by hand without the use of fast rotation such as a pottery wheel; some were brushed with red ochre. Pottery and permanent settlements have been thought of the three defining characteristics of the Woodland period. However, it has become evident that, in some areas of the United States, prehistoric cultural groups with a Archaic cultural assemblage were making pottery without any evidence of the cultivation of domesticated crops. In fact, it appears that hunting and gathering continued as the basic subsistence economy and that subsistence horticulture/agriculture did not occur in much of the Southeast for a couple of thousand years after the introduction of pottery, in parts of the Northeast, horticulture was never practiced.
This research indicated that a fiber-tempered horizon of ceramics predates 1000 BCE, first appearing about 2500 BCE in parts of Florida with the Orange culture and in Georgia with the Stallings culture. These early sites were typical Archaic settlements, differing only in the use of basic ceramic technology; as such, researchers are now redefining the period to begin with not only pottery, but the appearance of permanent settlements, elaborate burial practices, intensive collection and/or horticulture of starchy seed plants, differentiation in social organization, specialized activities, among other factors. Most of these are evident in the Southeastern United States by 1000 BCE. In some areas, like South Carolina and coastal Georgia, Deptford culture pottery manufacture ceased after c. 700 CE. In coastal regions, many settlements were near the coast near salt marshes, which were habitats ric
Flint is a hard, sedimentary cryptocrystalline form of the mineral quartz, categorized as a variety of chert. It occurs chiefly as nodules and masses such as chalks and limestones. Inside the nodule, flint is dark grey, green, white or brown in colour, has a glassy or waxy appearance. A thin layer on the outside of the nodules is different in colour white and rough in texture. From a petrological point of view, "flint" refers to the form of chert which occurs in chalk or marly limestone. "common chert" occurs in limestone. Flint is durable and can be found along streams and beaches, its use to make stone tools dates back millions of years. Due to some properties of flint it breaks into sharp edged pieces making it useful for knife blades and other sharp tools. During the Stone Age access to flint was so important for survival that people would travel or trade to obtain flint. Flint Ridge in eastern Ohio was an important source of flint and Native Americans extracted the flint from hundreds of quarries along the ridge.
This "Ohio Flint" was traded across the eastern United States and has been found as far west as the Rocky Mountains and south around the Gulf of Mexico. The exact mode of formation of flint is not yet clear, but it is thought that it occurs as a result of chemical changes in compressed sedimentary rock formations, during the process of diagenesis. One hypothesis is that a gelatinous material fills cavities in the sediment, such as holes bored by crustaceans or molluscs and that this becomes silicified; this hypothesis explains the complex shapes of flint nodules that are found. The source of dissolved silica in the porous media could be the spicules of silicious sponges. Certain types of flint, such as that from the south coast of England, contain trapped fossilised marine flora. Pieces of coral and vegetation have been found preserved like amber inside the flint. Thin slices of the stone reveal this effect. Puzzling giant flint formations known as paramoudra and flint circles are found around Europe but in Norfolk, England on the beaches at Beeston Bump and West Runton.
Flint sometimes occurs in large flint fields for example, in Europe. The "Ohio flint" is the official gemstone of Ohio state, it is formed from limey debris, deposited at the bottom of inland Paleozoic seas hundreds of millions of years ago that hardened into limestone and became infused with silica. The flint from Flint Ridge is found in many hues like red, pink, blue and gray, with the color variations caused by minute impurities of iron compounds. Flint was used in the manufacture of tools during the Stone Age as it splits into thin, sharp splinters called flakes or blades when struck by another hard object; this process is referred to as knapping. The process of making tools this way is called "flintknapping". In Europe, some of the best toolmaking flint has come from Belgium, the coastal chalks of the English Channel, the Paris Basin, Thy in Jutland, the Sennonian deposits of Rügen, Grimes Graves in England, the Upper Cretaceous chalk formation of Dobruja and the lower Danube, the Cenomanian chalky marl formation of the Moldavian Plateau and the Jurassic deposits of the Kraków area and Krzemionki in Poland, as well as of the Lägern in the Jura Mountains of Switzerland.
Flint mining became more common since the Neolithic. In 1938, a project of the Ohio Historical Society, under the leadership of H. Holmes Ellis began to study the flintknapping "methods and techniques" of Native Americans. Like past studies, this work involved experimenting with actual flintknapping techniques by creation of stone tools through the use of techniques like direct freehand percussion, freehand pressure and pressure using a rest. Other scholars who have conducted similar experiments and studies include William Henry Holmes, Alonzo W. Pond, Sir Francis H. S. Knowles and Don Crabtree; when struck against steel, a flint edge produces. The hard flint edge shaves off a particle of the steel that exposes iron, which reacts with oxygen from the atmosphere and can ignite the proper tinder. Prior to the wide availability of steel, rocks of pyrite would be used along with the flint, in a similar way; these methods are popular in woodcraft and amongst people practising traditional fire-starting skills.
A major use of flint and steel was in the flintlock mechanism, used in flintlock firearms, but used on dedicated fire-starting tools. A piece of flint held in the jaws of a spring-loaded hammer, when released by a trigger, strikes a hinged piece of steel at an angle, creating a shower of sparks and exposing a charge of priming powder; the sparks ignite the priming powder and that flame, in turn, ignites the main charge, propelling the ball, bullet, or shot through the barrel. While the military use of the flintlock declined after the adoption of the percussion cap from the 1840s onward, flintlock rifles and shotguns remain in use amongst recreational shooters. Flint and steel used to strike sparks were superseded by ferrocerium; this man-made material, when scraped with any hard, sharp edge, produces sparks that are much hotter than obtained with natural flint and steel, allowing use of a wider range of tinders. Because it can produce sparks when wet and can start fires
Archaic period (North America)
In the classification of the archaeological cultures of North America, the Archaic period or "Meso-Indian period" in North America, taken to last from around 8000 to 1000 BC in the sequence of North American pre-Columbian cultural stages, is a period defined by the archaic stage of cultural development. The Archaic stage is characterized by subsistence economies supported through the exploitation of nuts and shellfish; as its ending is defined by the adoption of sedentary farming, this date can vary across the Americas. The rest of the Americas have an Archaic Period; this classification system was first proposed by Gordon Willey and Philip Phillips in the accepted 1958 book Method and Theory in American Archaeology. In the organization of the system, the Archaic period followed the Lithic stage and is superseded by the Formative stage; the Lithic stage The Archaic stage The Formative stage The Classic stage The Post-Classic stageNumerous local variations have been identified within the cultural rankings.
The period has been subdivided by region and time. For instance, the Archaic Southwest tradition is subdivided into the Dieguito-Pinto, Oshara and Chihuahua cultures. Since the 1990s, secure dating of multiple Middle Archaic sites in northern Louisiana and Florida has challenged traditional models of development. In these areas, hunter-gatherer societies in the Lower Mississippi Valley organized to build monumental earthwork mound complexes as early as 3500 BC, with building continuing over a period of 500 years; such early mound sites as Frenchman's Bend and Hedgepeth were of this time period. Watson Brake is now considered to be the oldest mound complex in the Americas, it precedes. More than 100 sites have been identified as associated with the regional Poverty Point culture of the Late Archaic period, it was part of a regional trading network across the Southeast. Across what is now the Southeastern United States, starting around 4000 BC, people exploited wetland resources, creating large shell middens.
Middens developed where the people lived along rivers, but there is limited evidence of Archaic peoples along the coastlines prior to 3000 BC. Archaic sites on the coast may have been inundated by rising sea levels. Starting around 3000 BC, evidence of large-scale exploitation of oysters appears. During the period 3000 BC to 1000 BC, shell rings, large shell middens that more or less surround open centers, were developed along the coast of the Southeastern United States; these shell rings are numerous in South Carolina and Georgia, but are found scattered around the Florida Peninsula and along the Gulf of Mexico coast as far west as the Pearl River. In some places, such as Horr's Island in Southwest Florida, resources were rich enough to support sizable mound-building communities year-round. Four shell or sand mounds on Horr's Island have been dated to between 4,870 and 4,270 Before Present. Early Archaic8000 BC: The last glacial ends, causing sea levels to rise and flood the Beringia land bridge, closing the primary migration route from Siberia.
8000 BC: Sufficient rain falls on the American Southwest to support many large mammal species--mammoth, a bison species-—that soon go extinct. 8000 BC: Hunters in the American Southwest use the atlatl. 7500 BC: Early basketry. 7560—7370 BC: Kennewick Man dies along the shore of the Columbia River in Washington State, leaving one of the most complete early Native American skeletons. 7000 BC: Northeastern peoples depend on deer and wild grains as the climate warms. 7000 BC: Native Americans in Lahontan Basin, Nevada mummify their dead to give them honor and respect, evidencing deep concern about their treatment and condition. Middle Archaic6500 BC–200 AD: The San Dieguito-Pinto tradition and Chihuahua Tradition flourish in southern California, the Southwest, northwestern Mexico. 6000 BC: Ancestors of Penutian-speaking peoples settle in the Northwestern Plateau. 6000 BC: Nomadic hunting bands roam Subarctic Alaska following herds of caribou and other game animals. 6000 BC: Aleuts begin to arrive in the Aleutian Islands.
5700 BC: Cataclysmic eruption of Mount Mazama in Oregon. 5500 BC–500 AD Oshara Tradition, a Southwestern Archaic Tradition, arises in north-central New Mexico, the San Juan Basin, the Rio Grande Valley, southern Colorado, southeastern Utah. Natives of the Northwestern Plateau begin to rely on salmon runs. 5000 BC: Early cultivation of food crops began in Mesoamerica. 5000 BC: Native Americans in the Pacific Northwest from Alaska to California develop a fishing economy, with salmon as a staple. 5000 BC: The Old Copper Culture of the Great Lakes area hammers the metal into various tools and ornaments, such as knives, awls, bracelets and pendants. 5000 BC–200 AD: The Cochise Tradition arises in the American Southwest. Native Americans in the northern Great Lakes produce copper tools and utensils traded throughout the Great Plains and Ohio Valley. Shell ornaments and copper items at Indian Knoll in Kentucky evidence an extensive trade system over several millennia. 4000 BC: Inhabitants of Mesoamerica cultivate maize while Peruvian natives cultivate beans and squash.
4000–1000 BC: Old Copper Complex emerges in the Great Lakes region 3500 BC: The largest, oldest drive site at Head-Smashed-In Buffalo Jump, Canada. 3500–3000 BC: Construction of extensive mound complex built at Watson Brake in the floodplain of the Ouachita River near Monroe in northern Louisiana. Shell ornaments and copper items at Indian Knoll, Kentucky evi
Jaketown Site is an archaeological site with two prehistoric earthwork mounds in Humphreys County, United States. While the mounds have not been excavated, distinctive pottery sherds found in the area lead scholars to date the mounds' construction and use to the Mississippian culture period 1100 CE to 1500 CE; the site was a complex regional trade center that developed and was inhabited much earlier, from 2000-600 BCE, during the Poverty Point culture within the Late Archaic period of the United States. This culture is seen in more than 100 sites on both sides of the Mississippi River, from present-day Louisiana to Mississippi; the site has evidence of trade in raw materials and manufacture of finished items that were distributed through the network throughout the Eastern United States. The largest and most elaborate earthwork complex of the period is at Louisiana; the mounds were constructed as part of a succeeding culture, built to mark the political and religious center of a chiefdom. There would have been numerous elite residences nearby, as well as structures to support certain crafts.
Because of its importance of a regional trade center of the Poverty Point culture in the Archaic period, long human occupation, the site was declared a National Historic Landmark in 1990. It is managed by the state of Mississippi. Mississippi Highway 7 is routed near the site, seven miles north of Belzoni. Artifacts found in the area near the site are featured on display in the Jaketown Museum in Belzoni. Dating of the artifacts has demonstrated that the Jaketown site was occupied by indigenous peoples from 1750 BCE to 1500 CE, making it one of the oldest continuously inhabited sites in the region. Archeological investigations have found that the smaller mounds nearby were hundreds of years older than the surviving two, they were destroyed by plowing and being razed for use as fill for road construction in the early 20th century. The largest platform mound at the site, Mound B, is 23 feet in height with a base of 150 feet by 200 feet, it has a projection on its eastern side, thought to have been a ramp once used as a stairway.
To its northeast is Mound C, another platform mound with a height of 15 feet. List of Mississippian sites Jaketown Site - National Park Service Lee Arco: Geoarchaeology at Jaketown UM Museum of Anthropology
A pyramid is a structure whose outer surfaces are triangular and converge to a single point at the top, making the shape a pyramid in the geometric sense. The base of a pyramid can be quadrilateral, or of any polygon shape; as such, a pyramid has at least three outer triangular surfaces. The square pyramid, with a square base and four triangular outer surfaces, is a common version. A pyramid's design, with the majority of the weight closer to the ground, with the pyramidion on top, means that less material higher up on the pyramid will be pushing down from above; this distribution of weight allowed early civilizations to create stable monumental structures. Civilizations in many parts of the world have built pyramids; the largest pyramid by volume is the Great Pyramid of Cholula, in the Mexican state of Puebla. For thousands of years, the largest structures on Earth were pyramids—first the Red Pyramid in the Dashur Necropolis and the Great Pyramid of Khufu, both in Egypt—the latter is the only one of the Seven Wonders of the Ancient World still remaining.
The Mesopotamians built the earliest pyramidal structures, called ziggurats. In ancient times, these were brightly painted in gold/bronze. Since they were constructed of sun-dried mud-brick, little remains of them. Ziggurats were built by the Sumerians, Elamites and Assyrians for local religions; each ziggurat was part of a temple complex. The precursors of the ziggurat were raised platforms that date from the Ubaid period during the fourth millennium BC; the earliest ziggurats began near the end of the Early Dynastic Period. The latest Mesopotamian ziggurats date from the 6th century BC. Built in receding tiers upon a rectangular, oval, or square platform, the ziggurat was a pyramidal structure with a flat top. Sun-baked bricks made up the core of the ziggurat with facings of fired bricks on the outside; the facings were glazed in different colors and may have had astrological significance. Kings sometimes had their names engraved on these glazed bricks; the number of tiers ranged from two to seven.
It is assumed that they had shrines at the top, but there is no archaeological evidence for this and the only textual evidence is from Herodotus. Access to the shrine would have been by a series of ramps on one side of the ziggurat or by a spiral ramp from base to summit; the most famous pyramids are the Egyptian — huge structures built of brick or stone, some of which are among the world's largest constructions. They are shaped as a reference to the rays of the sun. Most pyramids had a polished reflective white limestone surface, to give them a shining appearance when viewed from a distance; the capstone was made of hard stone – granite or basalt – and could be plated with gold, silver, or electrum and would be reflective. After 2700 BC, the ancient Egyptians began building pyramids, until around 1700 BC; the first pyramid was erected during the Third Dynasty by the Pharaoh Djoser and his architect Imhotep. This step pyramid consisted of six stacked mastabas; the largest Egyptian pyramids are those at the Giza pyramid complex.
The Egyptian sun god Ra, considered the father of all pharaohs, was said to have created himself from a pyramid-shaped mound of earth before creating all other gods. The age of the pyramids reached its zenith at Giza in 2575–2150 BC. Ancient Egyptian pyramids were in most cases placed west of the river Nile because the divine pharaoh's soul was meant to join with the sun during its descent before continuing with the sun in its eternal round; as of 2008, some 135 pyramids have been discovered in Egypt. The Great Pyramid of Giza is one of the largest in the world, it was the tallest building in the world until Lincoln Cathedral was finished in 1311 AD. The base is over 52,600 square metres in area. While pyramids are associated with Egypt, the nation of Sudan has 220 extant pyramids, the most numerous in the world; the Great Pyramid of Giza is one of the Seven Wonders of the Ancient World. It is the only one to survive into modern times; the Ancient Egyptians covered the faces of pyramids with polished white limestone, containing great quantities of fossilized seashells.
Many of the facing stones have been removed and used for construction in Cairo. Most pyramids are located near Cairo, with only one royal pyramid being located south of Cairo, at the Abydos temple complex; the pyramid at Abydos, Egypt were commissioned by Ahmose I who founded the 18th Dynasty and the New Kingdom. The building of pyramids began in the Third Dynasty with the reign of King Djoser. Early kings such as Snefru built several pyramids, with subsequent kings adding to the number of pyramids until the end of the Middle Kingdom; the last king to build royal pyramids was Ahmose, with kings hiding their tombs in the hills, such as those in the Valley of the Kings in Luxor's West Bank. In Medinat Habu, or Deir el-Medina, smaller pyramids were built by individuals. Smaller pyramids were built by the Nubians who ruled Egypt in the Late Period, though their pyramids had steeper sides. Nubian pyramids were constructed at three sites in Sudan to serve as tombs for the kings and queens of Napata and Meroë.
The pyramids of Kush known as Nubian Pyramids, have different characteristics than the pyramids of Egypt. The Nubian pyramids were constructed at a steeper angle than Egyptian ones. Pyramids were still being built in Sudan as late as 200 AD. One of the unique structures of Igbo culture was the Nsude Pyramids, at the Nigerian town of Nsude, northern Igboland. Ten pyramidal structures were built of clay/mud; the first base section was 60 ft. in circumference and 3 ft. in he