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92-711: The painted limestone statue of Djoser, now in the Egyptian Museum in Cairo , is the oldest known life-sized Egyptian statue. Today, at the site in Saqqara where it was found, a plaster copy of it stands in place of the original. The statue was discovered during the Antiquities Service Excavations of 1924–1925. In contemporary inscriptions, he is called by his Horus name Netjerikhet , meaning "divine of body". Later sources, which include

184-455: A Mohs hardness of 2 to 4, dense limestone can have a crushing strength of up to 180 MPa . For comparison, concrete typically has a crushing strength of about 40 MPa. Although limestones show little variability in mineral composition, they show great diversity in texture. However, most limestone consists of sand-sized grains in a carbonate mud matrix. Because limestones are often of biological origin and are usually composed of sediment that

276-692: A New Kingdom reference to his construction, help confirm that Netjerikhet and Djoser are the same person. While Manetho names Necherophes and the Turin King List names Nebka as the first ruler of the Third Dynasty, many Egyptologists now believe Djoser was first king of this dynasty , pointing out that the order in which some predecessors of Khufu are mentioned in the Westcar Papyrus suggests Nebka should be placed between Djoser and Huni , not before Djoser. More significantly,

368-463: A bloom of cyanobacteria or microalgae . However, stable isotope ratios in modern carbonate mud appear to be inconsistent with either of these mechanisms, and abrasion of carbonate grains in high-energy environments has been put forward as a third possibility. Formation of limestone has likely been dominated by biological processes throughout the Phanerozoic , the last 540 million years of

460-453: A 'Nimaat-hap' as the mother of Khasekhemwy's children, while the other seal at Beit Khallaf names the same person as the 'mother of the dual-king'. Further archaeological evidence linking the reigns of the two pharaohs together are found at Shunet et-Zebib, which suggest that Djoser oversaw the burial of his predecessor. Ritual stone vessels found at the sites of the tombs – Khasekhemwy's tomb at Abydos and Djoser's tomb at Saqqara – of

552-605: A base measurement of c. 125 × 109 metres. It was tightly covered in finely polished, white limestone. Under the step pyramid, a large maze of long corridors and chambers was dug. The burial chamber lies in the midst of the subterranean complex; a 28 meter deep shaft that leads directly from the surface down to the burial chamber. The shaft entrance was sealed by a plug stone with a weight of 3.5 tons. The subterranean burial maze contains four magazine galleries, each pointing straight to one cardinal direction. The eastern gallery contained three limestone reliefs depicting king Djoser during

644-434: A carbonate rock outcrop can be estimated in the field by etching the surface with dilute hydrochloric acid. This etches away the calcite and aragonite, leaving behind any silica or dolomite grains. The latter can be identified by their rhombohedral shape. Crystals of calcite, quartz , dolomite or barite may line small cavities ( vugs ) in the rock. Vugs are a form of secondary porosity, formed in existing limestone by

736-616: A central quartz grain or carbonate mineral fragment. These likely form by direct precipitation of calcium carbonate onto the ooid. Pisoliths are similar to ooids, but they are larger than 2 mm in diameter and tend to be more irregular in shape. Limestone composed mostly of ooids is called an oolite or sometimes an oolitic limestone . Ooids form in high-energy environments, such as the Bahama platform, and oolites typically show crossbedding and other features associated with deposition in strong currents. Oncoliths resemble ooids but show

828-449: A change in environment that increases the solubility of calcite. Dense, massive limestone is sometimes described as "marble". For example, the famous Portoro "marble" of Italy is actually a dense black limestone. True marble is produced by recrystallization of limestone during regional metamorphism that accompanies the mountain building process ( orogeny ). It is distinguished from dense limestone by its coarse crystalline texture and

920-949: A composition reflecting the organisms that produced them and the environment in which they were produced. Low-magnesium calcite skeletal grains are typical of articulate brachiopods , planktonic (free-floating) foraminifera, and coccoliths . High-magnesium calcite skeletal grains are typical of benthic (bottom-dwelling) foraminifera, echinoderms , and coralline algae . Aragonite skeletal grains are typical of molluscs , calcareous green algae , stromatoporoids , corals , and tube worms . The skeletal grains also reflect specific geological periods and environments. For example, coral grains are more common in high-energy environments (characterized by strong currents and turbulence) while bryozoan grains are more common in low-energy environments (characterized by quiet water). Ooids (sometimes called ooliths) are sand-sized grains (less than 2mm in diameter) consisting of one or more layers of calcite or aragonite around

1012-412: A considerable fraction of the limestone bed. At depths greater than 1 km (0.62 miles), burial cementation completes the lithification process. Burial cementation does not produce stylolites. When overlying beds are eroded, bringing limestone closer to the surface, the final stage of diagenesis takes place. This produces secondary porosity as some of the cement is dissolved by rainwater infiltrating

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1104-483: A drop of dilute hydrochloric acid is dropped on it. Dolomite is also soft but reacts only feebly with dilute hydrochloric acid, and it usually weathers to a characteristic dull yellow-brown color due to the presence of ferrous iron. This is released and oxidized as the dolomite weathers. Impurities (such as clay , sand, organic remains, iron oxide , and other materials) will cause limestones to exhibit different colors, especially with weathered surfaces. The makeup of

1196-637: A few million years, as this is the most stable form of calcium carbonate. Ancient carbonate formations of the Precambrian and Paleozoic contain abundant dolomite, but limestone dominates the carbonate beds of the Mesozoic and Cenozoic . Modern dolomite is quite rare. There is evidence that, while the modern ocean favors precipitation of aragonite, the oceans of the Paleozoic and middle to late Cenozoic favored precipitation of calcite. This may indicate

1288-455: A few thousand years. As rainwater mixes with groundwater, aragonite and high-magnesium calcite are converted to low-calcium calcite. Cementing of thick carbonate deposits by rainwater may commence even before the retreat of the sea, as rainwater can infiltrate over 100 km (60 miles) into sediments beneath the continental shelf. As carbonate sediments are increasingly deeply buried under younger sediments, chemical and mechanical compaction of

1380-490: A high percentage of the mineral dolomite , CaMg(CO 3 ) 2 . Magnesian limestone is an obsolete and poorly-defined term used variously for dolomite, for limestone containing significant dolomite ( dolomitic limestone ), or for any other limestone containing a significant percentage of magnesium . Most limestone was formed in shallow marine environments, such as continental shelves or platforms , though smaller amounts were formed in many other environments. Much dolomite

1472-435: A limestone sample except in thin section and are less common in ancient limestones, possibly because compaction of carbonate sediments disrupts them. Limeclasts are fragments of existing limestone or partially lithified carbonate sediments. Intraclasts are limeclasts that originate close to where they are deposited in limestone, while extraclasts come from outside the depositional area. Intraclasts include grapestone , which

1564-471: A lower Mg/Ca ratio in the ocean water of those times. This magnesium depletion may be a consequence of more rapid sea floor spreading , which removes magnesium from ocean water. The modern ocean and the ocean of the Mesozoic have been described as "aragonite seas". Most limestone was formed in shallow marine environments, such as continental shelves or platforms . Such environments form only about 5% of

1656-525: A lower diversity of organisms and a greater fraction of silica and clay minerals characteristic of marls . The Green River Formation is an example of a prominent freshwater sedimentary formation containing numerous limestone beds. Freshwater limestone is typically micritic. Fossils of charophyte (stonewort), a form of freshwater green algae, are characteristic of these environments, where the charophytes produce and trap carbonates. Limestones may also form in evaporite depositional environments . Calcite

1748-523: A mechanism for dolomitization, with one 2004 review paper describing it bluntly as "a myth". Ordinary seawater is capable of converting calcite to dolomite, if the seawater is regularly flushed through the rock, as by the ebb and flow of tides (tidal pumping). Once dolomitization begins, it proceeds rapidly, so that there is very little carbonate rock containing mixed calcite and dolomite. Carbonate rock tends to be either almost all calcite/aragonite or almost all dolomite. About 20% to 25% of sedimentary rock

1840-448: A plausible source of mud. Another possibility is direct precipitation from the water. A phenomenon known as whitings occurs in shallow waters, in which white streaks containing dispersed micrite appear on the surface of the water. It is uncertain whether this is freshly precipitated aragonite or simply material stirred up from the bottom, but there is some evidence that whitings are caused by biological precipitation of aragonite as part of

1932-449: A radial rather than layered internal structure, indicating that they were formed by algae in a normal marine environment. Peloids are structureless grains of microcrystalline carbonate likely produced by a variety of processes. Many are thought to be fecal pellets produced by marine organisms. Others may be produced by endolithic (boring) algae or other microorganisms or through breakdown of mollusc shells. They are difficult to see in

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2024-528: A regnal period of 18 partial or complete years. Rice further states that Nebkha was Djoser's brother and predecessor. Writer Farid Atiya provides a similar regnal period to Fletcher and Rice, offset by a single year – 2668 BC to 2649 BC. This dating is supported by authors Rosalie and Charles Baker in Ancient Egypt: People of the Pyramids . Egyptologist Abeer el-Shahawy in association with

2116-521: A resemblance to Khasekhem seat. One of the oldest representations of the Nine bows , and the first representation of the nine bows fully developed, is on the seated statue of Pharaoh Djoser. His feet rest upon part of the nine bows, which may have referred to Nubians during his reign because of their use of bows and arrows. The funerary complex is the first architectural project to be built entirely out of stone. This complex had fourteen entrances but only one

2208-438: A right angle to the west. Shafts I–V were used for the burials of royal family members; shafts VI–XI were used as symbolic tombs for the grave goods of royal ancestors from dynasties I–II. More than 40,000 vessels, bowls and vases made of various kinds of stone were found in these galleries. Royal names such as of kings Den , Semerkhet , Nynetjer and Sekhemib were incised on the pots. It is now thought that Djoser once restored

2300-531: A story called " Khufu and the magicians". But because the papyrus is badly damaged at the beginning, Imhotep's name is lost today. A papyrus from the ancient Egyptian temple of Tebtunis , dating to the 2nd century AD, preserves a long story in the demotic script about Djoser and Imhotep. In Djoser's time, Imhotep was of such importance and fame that he was honoured by being mentioned on statues of King Djoser in his necropolis at Saqqara. Egyptian historian Al-Nuwayri (1279–1333) described Djoser as "a king who

2392-416: Is a type of carbonate sedimentary rock which is the main source of the material lime . It is composed mostly of the minerals calcite and aragonite , which are different crystal forms of CaCO 3 . Limestone forms when these minerals precipitate out of water containing dissolved calcium. This can take place through both biological and nonbiological processes, though biological processes, such as

2484-560: Is also favored on the seaward margin of shelves and platforms, where there is upwelling deep ocean water rich in nutrients that increase organic productivity. Reefs are common here, but when lacking, ooid shoals are found instead. Finer sediments are deposited close to shore. The lack of deep sea limestones is due in part to rapid subduction of oceanic crust, but is more a result of dissolution of calcium carbonate at depth. The solubility of calcium carbonate increases with pressure and even more with higher concentrations of carbon dioxide, which

2576-482: Is an uncommon mineral in limestone, and siderite or other carbonate minerals are rare. However, the calcite in limestone often contains a few percent of magnesium . Calcite in limestone is divided into low-magnesium and high-magnesium calcite, with the dividing line placed at a composition of 4% magnesium. High-magnesium calcite retains the calcite mineral structure, which is distinct from dolomite. Aragonite does not usually contain significant magnesium. Most limestone

2668-402: Is carbonate rock, and most of this is limestone. Limestone is found in sedimentary sequences as old as 2.7 billion years. However, the compositions of carbonate rocks show an uneven distribution in time in the geologic record. About 95% of modern carbonates are composed of high-magnesium calcite and aragonite. The aragonite needles in carbonate mud are converted to low-magnesium calcite within

2760-474: Is clusters of peloids cemented together by organic material or mineral cement. Extraclasts are uncommon, are usually accompanied by other clastic sediments, and indicate deposition in a tectonically active area or as part of a turbidity current . The grains of most limestones are embedded in a matrix of carbonate mud. This is typically the largest fraction of an ancient carbonate rock. Mud consisting of individual crystals less than 5 μm (0.20 mils) in length

2852-416: Is commonly white to gray in color. Limestone that is unusually rich in organic matter can be almost black in color, while traces of iron or manganese can give limestone an off-white to yellow to red color. The density of limestone depends on its porosity, which varies from 0.1% for the densest limestone to 40% for chalk. The density correspondingly ranges from 1.5 to 2.7 g/cm . Although relatively soft, with

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2944-420: Is controlled largely by the amount of dissolved carbon dioxide ( CO 2 ) in the water. This is summarized in the reaction: Increases in temperature or decreases in pressure tend to reduce the amount of dissolved CO 2 and precipitate CaCO 3 . Reduction in salinity also reduces the solubility of CaCO 3 , by several orders of magnitude for fresh water versus seawater. Near-surface water of

3036-545: Is converted to low-magnesium calcite. Diagenesis is the likely origin of pisoliths , concentrically layered particles ranging from 1 to 10 mm (0.039 to 0.394 inches) in diameter found in some limestones. Pisoliths superficially resemble ooids but have no nucleus of foreign matter, fit together tightly, and show other signs that they formed after the original deposition of the sediments. Silicification occurs early in diagenesis, at low pH and temperature, and contributes to fossil preservation. Silicification takes place through

3128-503: Is deposited close to where it formed, classification of limestone is usually based on its grain type and mud content. Most grains in limestone are skeletal fragments of marine organisms such as coral or foraminifera . These organisms secrete structures made of aragonite or calcite, and leave these structures behind when they die. Other carbonate grains composing limestones are ooids , peloids , and limeclasts ( intraclasts and extraclasts  [ ca ] ). Skeletal grains have

3220-460: Is described as coquinite . Chalk is a soft, earthy, fine-textured limestone composed of the tests of planktonic microorganisms such as foraminifera, while marl is an earthy mixture of carbonates and silicate sediments. Limestone forms when calcite or aragonite precipitate out of water containing dissolved calcium, which can take place through both biological and nonbiological processes. The solubility of calcium carbonate ( CaCO 3 )

3312-617: Is described as micrite . In fresh carbonate mud, micrite is mostly small aragonite needles, which may precipitate directly from seawater, be secreted by algae, or be produced by abrasion of carbonate grains in a high-energy environment. This is converted to calcite within a few million years of deposition. Further recrystallization of micrite produces microspar , with grains from 5 to 15 μm (0.20 to 0.59 mils) in diameter. Limestone often contains larger crystals of calcite, ranging in size from 0.02 to 0.1 mm (0.79 to 3.94 mils), that are described as sparry calcite or sparite . Sparite

3404-462: Is distinguished from micrite by a grain size of over 20 μm (0.79 mils) and because sparite stands out under a hand lens or in thin section as white or transparent crystals. Sparite is distinguished from carbonate grains by its lack of internal structure and its characteristic crystal shapes. Geologists are careful to distinguish between sparite deposited as cement and sparite formed by recrystallization of micrite or carbonate grains. Sparite cement

3496-560: Is one of the first minerals to precipitate in marine evaporites. Most limestone is formed by the activities of living organisms near reefs, but the organisms responsible for reef formation have changed over geologic time. For example, stromatolites are mound-shaped structures in ancient limestones, interpreted as colonies of cyanobacteria that accumulated carbonate sediments, but stromatolites are rare in younger limestones. Organisms precipitate limestone both directly as part of their skeletons, and indirectly by removing carbon dioxide from

3588-473: Is otherwise chemically fairly pure, with clastic sediments (mainly fine-grained quartz and clay minerals ) making up less than 5% to 10% of the composition. Organic matter typically makes up around 0.2% of a limestone and rarely exceeds 1%. Limestone often contains variable amounts of silica in the form of chert or siliceous skeletal fragments (such as sponge spicules, diatoms , or radiolarians ). Fossils are also common in limestone. Limestone

3680-472: Is produced by decaying organic matter settling into the deep ocean that is not removed by photosynthesis in the dark depths. As a result, there is a fairly sharp transition from water saturated with calcium carbonate to water unsaturated with calcium carbonate, the lysocline , which occurs at the calcite compensation depth of 4,000 to 7,000 m (13,000 to 23,000 feet). Below this depth, foraminifera tests and other skeletal particles rapidly dissolve, and

3772-460: Is rejected by several Egyptologists, because another ancient Egyptian source, the Turin canon , credits Khufu with a reign of merely 23 years. At the opposite, the ancient Greek historian Herodotus claims that Khufu ruled for 50 years, which is now seen as an exaggeration. Meanwhile, today Egyptologists such as Thomas Schneider assume that either Khufu indeed ruled for a little over 34 years, or that

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3864-518: Is secondary dolomite, formed by chemical alteration of limestone. Limestone is exposed over large regions of the Earth's surface, and because limestone is slightly soluble in rainwater, these exposures often are eroded to become karst landscapes. Most cave systems are found in limestone bedrock. Limestone has numerous uses: as a chemical feedstock for the production of lime used for cement (an essential component of concrete ), as aggregate for

3956-552: Is the case of king Khufu ( 4th Dynasty ). The highest known numbers of cattle counts under Khufu are found in workmen's graffiti inside the relieving chambers of the Khufu pyramid . The ink inscription reports the "17th occasion of the cattle count". Since the Palermo stone inscriptions hold that the cattle count was performed every second year during the 4th Dynasty, it would prove that Khufu ruled at least 34 years. This calculation

4048-458: The Egyptian Museum in Cairo places Djoser's reign to the period of 2687 BC to 2668 BC for a similar 18 partial or complete years. Author Margaret Bunson places Djoser as the second ruler of the Third Dynasty, and places his reign to the period of 2630 BC to 2611 BC for 19 partial or complete year reign. In her chronology, Djoser is preceded by Nebka as the "Founder of the Third Dynasty", reigning for

4140-406: The cattle count was one of the two main means of evaluating the amount of taxes to be levied, the other one being the height of the annual inundation . A very important economic event, the cattle count was controlled by high officials, and was connected to several cultic feasts. In addition it served as a means of dating other events, with the entire year when it occurred being called "year of

4232-530: The "mother of the king's children, Nimaat-hap". On mastaba K1 at Beit Khallaf, the same person is mentioned as the "mother of the dual king". Dating of other seals at the Beit Khallaf site place them to the reign of Djoser. This evidence suggests that Khasekhemwy is either the direct father of Djoser or that Nimaat-hap had him through a previous husband. German Egyptologist Gunter Dreyer found Djoser's sealings at Khasekhemwy's tomb, further suggesting that Djoser

4324-496: The Earth's history. Limestone may have been deposited by microorganisms in the Precambrian , prior to 540 million years ago, but inorganic processes were probably more important and likely took place in an ocean more highly oversaturated in calcium carbonate than the modern ocean. Diagenesis is the process in which sediments are compacted and turned into solid rock . During diagenesis of carbonate sediments, significant chemical and textural changes take place. For example, aragonite

4416-787: The English Egyptologist Toby Wilkinson has demonstrated that burial seals found at the entrance to Khasekhemwy 's tomb in Abydos name only Djoser, rather than Nebka. This supports the view that it was Djoser who buried and, hence, directly succeeded Khasekhemwy, rather than Nebka. Djoser is linked to Khasekhemwy , the last king of the Second Dynasty of Egypt , through his wife Queen Nimaethap (Nimaat-hap) via seals found in Khasekhemwy's tomb and at Beit Khallaf . The seal at Abydos names Nimaat-hap as

4508-538: The Xth cattle count under the person of the king Y". The frequency of cattle counts varied through the history of ancient Egypt; in the Old Kingdom it was most likely biennial, i.e. occurring every two years, and became more frequent subsequently. To perform the cattle count, all chattel (including productive livestock such as cows and oxen , sheep , pigs , goats and donkeys ) were rounded up and counted. Following

4600-430: The accumulation of corals and shells in the sea, have likely been more important for the last 540 million years. Limestone often contains fossils which provide scientists with information on ancient environments and on the evolution of life. About 20% to 25% of sedimentary rock is carbonate rock, and most of this is limestone. The remaining carbonate rock is mostly dolomite , a closely related rock, which contains

4692-402: The assessment and levying of taxes by the central administration. The cattle count is of great importance to Egyptologists and historians , because many inscriptions report the year of the x-th occasion of the cattle count followed by the name of a pharaoh. Thus these inscriptions are used to assess the minimum duration of the reign of the pharaoh, for example assuming that the cattle count

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4784-434: The base of roads, as white pigment or filler in products such as toothpaste or paint, as a soil conditioner , and as a popular decorative addition to rock gardens . Limestone formations contain about 30% of the world's petroleum reservoirs . Limestone is composed mostly of the minerals calcite and aragonite , which are different crystal forms of calcium carbonate ( CaCO 3 ). Dolomite , CaMg(CO 3 ) 2 ,

4876-657: The beds. This may include the formation of vugs , which are crystal-lined cavities within the limestone. Diagenesis may include conversion of limestone to dolomite by magnesium-rich fluids. There is considerable evidence of replacement of limestone by dolomite, including sharp replacement boundaries that cut across bedding. The process of dolomitization remains an area of active research, but possible mechanisms include exposure to concentrated brines in hot environments ( evaporative reflux ) or exposure to diluted seawater in delta or estuary environments ( Dorag dolomitization ). However, Dorag dolomitization has fallen into disfavor as

4968-605: The beginning and ending of Djoser's reign, would most likely indicate his regnal years 1–5 and 19–28. Unfortunately, next to all entries are illegible today. The Year of coronation is preserved, followed by the year events receiving the twin-pillars and stretching the cords for the fortress Qau-Netjerw ("hills of the gods") . Various sources provide various dates for Djoser's reign. Professor of Ancient Near East history Marc van de Mieroop dates Djoser's reign to somewhere between 2686 BC to 2648 BC. Authors Joann Fletcher and Michael Rice date his reign from 2667 BC to 2648 BC giving

5060-481: The bottom with the concave face downwards. This traps a void space that can later be filled by sparite. Geologists use geopetal structures to determine which direction was up at the time of deposition, which is not always obvious with highly deformed limestone formations. The cyanobacterium Hyella balani can bore through limestone; as can the green alga Eugamantia sacculata and the fungus Ostracolaba implexa . Cattle count (Egypt) In ancient Egypt ,

5152-405: The building constructions was the high lector priest Imhotep . The step pyramid is made of limestone . It is massive and contains only one tight corridor leading to the close midst of the monument, ending in a rough chamber where the entrance to the tomb shaft was hidden. This inner construction was later filled with rubble, for it was of no use anymore. The pyramid was once 62 metres high and had

5244-475: The celebration of the Heb-Sed (rejuvenation feast). The walls around and between these reliefs were decorated with bluish faience tiles. They were thought to imitate reed mats, as an allusion to the mythological underworld waters. The other galleries remained unfinished. At the eastern side of the pyramid, very close to the blue chambers, eleven tomb shafts lead straight down for 30–32 metres, and then deviate in

5336-419: The count, the percentage of chattel to be taxed by the state would be calculated. The cattle count was performed in every nome of Egypt. Fraud was harshly punished. From the 2nd Dynasty onwards, the cattle count was connected with the "Following of Horus " (Egypt. Shemsu Hor ) which occurred every two years. The Shemsu Hor consisted of a journey by the king and his court throughout Egypt which facilitated

5428-466: The depositional fabric of carbonate rocks. Dunham divides the rocks into four main groups based on relative proportions of coarser clastic particles, based on criteria such as whether the grains were originally in mutual contact, and therefore self-supporting, or whether the rock is characterized by the presence of frame builders and algal mats. Unlike the Folk scheme, Dunham deals with the original porosity of

5520-469: The deposits are highly porous, so that they have a spongelike texture, they are typically described as tufa . Secondary calcite deposited by supersaturated meteoric waters ( groundwater ) in caves is also sometimes described as travertine. This produces speleothems , such as stalagmites and stalactites . Coquina is a poorly consolidated limestone composed of abraded pieces of coral , shells , or other fossil debris. When better consolidated, it

5612-406: The earth's oceans are oversaturated with CaCO 3 by a factor of more than six. The failure of CaCO 3 to rapidly precipitate out of these waters is likely due to interference by dissolved magnesium ions with nucleation of calcite crystals, the necessary first step in precipitation. Precipitation of aragonite may be suppressed by the presence of naturally occurring organic phosphates in

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5704-399: The first refers to the grains and the second to the cement. For example, a limestone consisting mainly of ooids, with a crystalline matrix, would be termed an oosparite. It is helpful to have a petrographic microscope when using the Folk scheme, because it is easier to determine the components present in each sample. Robert J. Dunham published his system for limestone in 1962. It focuses on

5796-572: The formation of distinctive minerals from the silica and clay present in the original limestone. Two major classification schemes, the Folk and Dunham, are used for identifying the types of carbonate rocks collectively known as limestone. Robert L. Folk developed a classification system that places primary emphasis on the detailed composition of grains and interstitial material in carbonate rocks . Based on composition, there are three main components: allochems (grains), matrix (mostly micrite), and cement (sparite). The Folk system uses two-part names;

5888-429: The geologic record are called bioherms . Many are rich in fossils, but most lack any connected organic framework like that seen in modern reefs. The fossil remains are present as separate fragments embedded in ample mud matrix. Much of the sedimentation shows indications of occurring in the intertidal or supratidal zones, suggesting sediments rapidly fill available accommodation space in the shelf or platform. Deposition

5980-427: The late Old Kingdom . After this period, however, it was performed more frequently and finally yearly. The first pharaoh during whose reign yearly cattle counts are known to have taken place with certainty is king Pepi I of the 6th Dynasty . This does not exclude that the cattle count necessarily took place every second year before Pepi I. An example of conflicting evaluations for a reign duration via cattle count

6072-412: The medieval Arabic sources, which show them as heroes, with their names and deeds well recognised by the writers". Djoser was buried in his famous step pyramid at Saqqara. This pyramid was originally built as a nearly square mastaba , but then five further mastabas were literally piled one upon another, each smaller than the previous one, until the monument became Egypt's first step pyramid. Supervisor of

6164-410: The ocean basins, but limestone is rarely preserved in continental slope and deep sea environments. The best environments for deposition are warm waters, which have both a high organic productivity and increased saturation of calcium carbonate due to lower concentrations of dissolved carbon dioxide. Modern limestone deposits are almost always in areas with very little silica-rich sedimentation, reflected in

6256-416: The original tombs of the ancestors, and then sealed the grave goods in the galleries in an attempt to save them. The statue of Djoser is walled into the serdab. The main purpose of the statue was to allow the king to manifest himself and be able to see the rituals performed in and out the serdab. This painted statue is plastered and made out of limestone. Each characteristic of the statue represents something,

6348-472: The period 2649 BC to 2630 BC. She, like Rice, makes Nebka a brother of Djoser. Djoser dispatched several military expeditions to the Sinai Peninsula , during which the local inhabitants were subdued. He also sent expeditions there to mine for valuable minerals such as turquoise and copper . This is known from inscriptions found in the desert there, sometimes displaying the banner of Set alongside

6440-656: The physician Aesculapius , and for introducing some reforms in the writing system. Modern scholars think that Manetho originally ascribed (or meant to ascribe) these feats to Imuthes , who was later deified as Aesculapius by the Greeks and Romans, and who corresponds to Imhotep , the famous minister of Djoser who engineered the Step Pyramid's construction. Some fragmentary reliefs found at Heliopolis and Gebelein mention Djoser's name, and suggest he commissioned construction projects in those cities. Also, he may have fixed

6532-426: The reaction: Fossils are often preserved in exquisite detail as chert. Cementing takes place rapidly in carbonate sediments, typically within less than a million years of deposition. Some cementing occurs while the sediments are still under water, forming hardgrounds . Cementing accelerates after the retreat of the sea from the depositional environment, as rainwater infiltrates the sediment beds, often within just

6624-482: The relative purity of most limestones. Reef organisms are destroyed by muddy, brackish river water, and carbonate grains are ground down by much harder silicate grains. Unlike clastic sedimentary rock, limestone is produced almost entirely from sediments originating at or near the place of deposition. Limestone formations tend to show abrupt changes in thickness. Large moundlike features in a limestone formation are interpreted as ancient reefs , which when they appear in

6716-460: The rock. The Dunham scheme is more useful for hand samples because it is based on texture, not the grains in the sample. A revised classification was proposed by Wright (1992). It adds some diagenetic patterns to the classification scheme. Travertine is a term applied to calcium carbonate deposits formed in freshwater environments, particularly waterfalls , cascades and hot springs . Such deposits are typically massive, dense, and banded. When

6808-414: The same person. Egyptologist Toby Wilkinson believes that the weight of archeological evidence favours Djoser (Netjerikhet) as Khasekhemwy's successor and therefore founder of the Third Dynasty. A seal from Khasekhemwy's tomb at Abydos, in combination with a seal from mastaba K1 at Beit Khallaf dated to Djoser's reign, links the two pharaohs together as father and son respectively. The seal at Abydos names

6900-479: The sediments increases. Chemical compaction takes place by pressure solution of the sediments. This process dissolves minerals from points of contact between grains and redeposits it in pore space, reducing the porosity of the limestone from an initial high value of 40% to 80% to less than 10%. Pressure solution produces distinctive stylolites , irregular surfaces within the limestone at which silica-rich sediments accumulate. These may reflect dissolution and loss of

6992-662: The sediments of the ocean floor abruptly transition from carbonate ooze rich in foraminifera and coccolith remains ( Globigerina ooze) to silicic mud lacking carbonates. In rare cases, turbidites or other silica-rich sediments bury and preserve benthic (deep ocean) carbonate deposits. Ancient benthic limestones are microcrystalline and are identified by their tectonic setting. Fossils typically are foraminifera and coccoliths. No pre-Jurassic benthic limestones are known, probably because carbonate-shelled plankton had not yet evolved. Limestones also form in freshwater environments. These limestones are not unlike marine limestone, but have

7084-412: The shift to a more northerly capital was completed during Djoser's time. One of the most famous contemporaries of king Djoser was his vizier ( tjaty ), "head of the royal shipyard " and "overseer of all stone works", Imhotep . Imhotep oversaw stone building projects such as the tombs of King Djoser and King Sekhemkhet. It is possible that Imhotep was mentioned in the also famous Westcar Papyrus , in

7176-707: The southern boundary of his kingdom at the First Cataract . An inscription known as the Famine Stela and claiming to date to the reign of Djoser, but probably created during the Ptolemaic Dynasty , relates how Djoser rebuilt the temple of Khnum on the island of Elephantine at the First Cataract, thus ending a seven-year famine in Egypt. Some consider this ancient inscription as a legend at

7268-449: The striated tripartite wig he is wearing assimilates him to the living world as a dead king. The striped head cloth that covers the wig was used to cover all of his hair. This was a ritual that began to be used by kings in the fourth dynasty. The body is wrapped under a long robe, his hands are placed in a specific way. His right arm is horizontally displayed on his chest while his left arm is resting on his thigh. The placement of his arms are

7360-611: The symbols of Horus , as had been more common under Khasekhemwy. The Sinai was also strategically important as a buffer between the Nile valley and Asia. His most famous monument was his step pyramid , which entailed the construction of several mastaba tombs one over another. These forms would eventually lead to the standard pyramid tomb in the later Old Kingdom . Manetho, many centuries later, alludes to architectural advances of this reign, mentioning that "Tosorthros" discovered how to build with hewn stone, in addition to being remembered as

7452-477: The time it was inscribed. Nonetheless, it does show that more than two millennia after his reign, Egyptians still remembered Djoser. Although he seems to have started an unfinished tomb at Abydos (Upper Egypt), Djoser was eventually buried in his famous pyramid at Saqqara in Lower Egypt. Since Khasekhemwy, a pharaoh from the 2nd dynasty, was the last pharaoh to be buried at Abydos, some Egyptologists infer that

7544-479: The two pharaohs also appear to have come from the same collection, as samples from both sites contain identical imagery of the god Min. This archeological evidence is supplemented by at least one historical source, the Saqqara king list, which names Djoser as the immediate successor of Beby – a misreading of Khasekhemwy. Manetho states Djoser ruled Egypt for twenty-nine years, while the Turin King List states it

7636-533: The water by photosynthesis and thereby decreasing the solubility of calcium carbonate. Limestone shows the same range of sedimentary structures found in other sedimentary rocks. However, finer structures, such as lamination , are often destroyed by the burrowing activities of organisms ( bioturbation ). Fine lamination is characteristic of limestone formed in playa lakes , which lack the burrowing organisms. Limestones also show distinctive features such as geopetal structures , which form when curved shells settle to

7728-553: The water. Although ooids likely form through purely inorganic processes, the bulk of CaCO 3 precipitation in the oceans is the result of biological activity. Much of this takes place on carbonate platforms . The origin of carbonate mud, and the processes by which it is converted to micrite, continue to be a subject of research. Modern carbonate mud is composed mostly of aragonite needles around 5 μm (0.20 mils) in length. Needles of this shape and composition are produced by calcareous algae such as Penicillus , making this

7820-641: Was a wise ruler of Egypt" and claimed that the Copts had a feast in honour of him called the "vine festival". Al-Nuwayri also visited the South tomb of the pyramid complex of Djoser in Saqqara , identifying it as the tomb of "Zosara" and describing a vault decorated with lapis lazuli , as well as a large court with a large granite door inscribed with 30 lines of hieroglyphs . Egyptologist Okasha El-Daly noted that " Demotic romances of ancient Egyptian rulers such as Zoser, Inaros and Nectanebo also became popular in

7912-582: Was functional. It is made up of the Great South Court, and the Heb-sed north court with Djoser's step pyramid in the center. The complex is enclosed by a 10.5 meters high stone wall, referred to as the enclosure wall. Along with the main courts there is a Roofed Colonnade Entrance located within the south court and a Serdab chamber that holds the seated statue of the king Djoser. Limestone Limestone ( calcium carbonate CaCO 3 )

8004-484: Was held every two years. This last point being of paramount importance for correct datation of reign lengths, it is highly disputed up to this day. According to the Palermo stone , a black basalt stone slab recording the yearly events of cultic and religious nature from king Narmer ( 1st Dynasty ) down to king Neferirkare Kakai (3rd pharaoh of the 5th Dynasty ), the cattle count was performed every second year until

8096-416: Was likely deposited in pore space between grains, suggesting a high-energy depositional environment that removed carbonate mud. Recrystallized sparite is not diagnostic of depositional environment. Limestone outcrops are recognized in the field by their softness (calcite and aragonite both have a Mohs hardness of less than 4, well below common silicate minerals) and because limestone bubbles vigorously when

8188-564: Was one of prosperity, marked by the start of the Third Dynasty and the Old Kingdom of Egypt. The exact identity of the founder of the dynasty is a matter of debate, due to the fragmentary nature of the records from the period. Djoser is one of the principal candidates for the founder of the Third Dynasty. Other candidates are Nebka and Sanakht . Complicating matters further is the possibility that Nebka and Sanakht are referring to

8280-611: Was only nineteen years. Because of his many substantial building projects, particularly at Saqqara, some scholars argue Djoser must have enjoyed a reign of nearly three decades. Manetho's figure appears to be more accurate, according to Wilkinson's analysis and reconstruction of the Royal Annals. Wilkinson reconstructs the Annals as giving Djoser " 28 complete or partial years ", noting that the cattle counts recorded on Palermo stone register V, and Cairo Fragment 1 , register V, for

8372-480: Was the direct successor of Khasekhemwy and that he finished the construction of the tomb. Her cult seems to have still been active in the later reign of Sneferu . Hetephernebti is identified as one of Djoser's queens "on a series of boundary stela from the Step Pyramid enclosure (now in various museums) and a fragment of relief from a building at Hermopolis" currently in the Egyptian museum of Turin. Inetkawes

8464-399: Was their only daughter known by name. There was also a third royal female attested during Djoser's reign, but her name is destroyed. The relationship between Djoser and his successor, Sekhemkhet , is not known, and the date of his death is uncertain. The lands of Upper and Lower Egypt were united into a single kingdom sometime around 2686 BC. The period following the unification of the crowns

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