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73-404: Chemically, gypsum is a hydrous sulfate of calcium , whereas calcite is a carbonate of calcium. As types of alabaster, gypsum and calcite have similar properties, such as light color, translucence, and soft stones that can be carved and sculpted ; thus the historical use and application of alabaster for the production of carved, decorative artefacts and objets d’art . Calcite alabaster also

146-476: A recommended exposure limit (REL) of 10 mg/m total exposure and 5 mg/m respiratory exposure over an 8-hour workday. Dust, debris and temperature fluctuations from working marble can endanger the eye health of employees. For the staff involved in marble processing, it is necessary to provide eye protection equipment, and it is recommended to improve the education of all workers on occupational health risks and strengthen preventive measures. As

219-478: A delicate green variety at La Pedrara , in the district of Tecali , near Puebla . Onyx-marble occurs also in the district of Tehuacán and at several localities in the US including California , Arizona , Utah , Colorado and Virginia . Gypsum alabaster is softer than calcite alabaster. It was used primarily in medieval Europe, and is also used in modern times. "Mosul marble" is a kind of gypsum alabaster found in

292-570: A growth of 12% annually for the 2000–2006 period, compared to 10.5% annually for the 2000–2005 period. The largest dimension marble application is tile. The stone and marble industry is one of the largest industries in Palestine, contributing 20-25% of its total industrial revenues, generating USD $ 400–$ 450 million in revenue annually. The industry employs 15,000–20,000 workers across the West Bank across 1200–1700 facilities, and amounts to 4.5% of

365-646: A potential hazard. Mitigations such as dust filters, or dust suppression are suggested, but more research needs to be carried out on the efficacy of safety measures. In the United States, the Occupational Safety and Health Administration (OSHA) has set the legal limit ( permissible exposure limit ) for marble exposure in the workplace as 15 mg/m total exposure and 5 mg/m respiratory exposure over an 8-hour workday. The National Institute for Occupational Safety and Health (NIOSH) has set

438-399: A smooth, polished surface is washed with dishwashing liquid , it will become rough, dull and whiter, losing most of its translucency and lustre. The finer kinds of alabaster are employed largely as an ornamental stone , especially for ecclesiastical decoration and for the rails of staircases and halls. Alabaster is mined and then sold in blocks to alabaster workshops. There they are cut to

511-425: A typical process using magnesium fluorosilicate (MgSiF 6 ) and hydrochloric acid (HCl) taking place. The resulting calcium hexafluorosilicate (CaSiF 6 ) is bonded to the surface of the marble. This is harder, more glossy and stain resistant compared to the original surface. The other often used method of finishing marble is to polish with oxalic acid (H 2 C 2 O 4 ), an organic acid. The resulting reaction

584-420: A variety of hydrates, each of which crystallizes in only one form. The sulfate group often binds to the metal, especially for those salts with fewer than six aquo ligands . The heptahydrates, which are often the most common salts, crystallize as monoclinic and the less common orthorhombic forms. In the heptahydrates, one water is in the lattice and the other six are coordinated to the ferrous center. Many of

657-507: A variety of indoor artwork and carving, as they will not survive long outdoors. The two types are readily distinguished by their different hardness: gypsum alabaster ( Mohs hardness 1.5 to 2) is so soft that a fingernail scratches it, while calcite (Mohs hardness 3) cannot be scratched in this way but yields to a knife. Moreover, calcite alabaster, being a carbonate, effervesces when treated with hydrochloric acid , while gypsum alabaster remains almost unaffected. The English word "alabaster"

730-467: Is a metamorphic rock consisting of carbonate minerals (most commonly calcite (CaCO 3 ) or dolomite (CaMg(CO 3 ) 2 ) that have recrystallized under the influence of heat and pressure. It has a crystalline texture, and is typically not foliated ( layered ), although there are exceptions. In geology , the term marble refers to metamorphosed limestone , but its use in stonemasonry more broadly encompasses unmetamorphosed limestone. Marble

803-495: Is a porous stone and can be "dyed" into any colour or shade, a technique used for centuries. For this the stone needs to be fully immersed in various pigmentary solutions and heated to a specific temperature. The technique can be used to disguise alabaster. In this way a very misleading imitation of coral that is called "alabaster coral" is produced. Typically only one type is sculpted in any particular cultural environment, but sometimes both have been worked to make similar pieces in

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876-399: Is a rock composed of calcium and magnesium carbonate , mostly white and pink. Common marble varieties are granular limestone or dolomite . The hardness of marble is very high, because the internal structure of the rock is very uniform after long-term natural aging, and the internal stress disappears, so the marble will not be deformed due to temperature, and has strong wear resistance. It

949-439: Is a very popular building material. The following table is a summary of the features of Marble. White marble has been prized for its use in sculptures since classical times . This preference has to do with its softness, which made it easier to carve, relative isotropy and homogeneity, and a relative resistance to shattering. Also, the low index of refraction of calcite allows light to penetrate 12.7 to 38 millimeters into

1022-585: Is also found, in smaller quantity, at Watchet in Somerset , near Penarth in Glamorganshire , and elsewhere. In Cumbria it occurs largely in the New Red rocks, but at a lower geological horizon. The alabaster of Nottinghamshire and Derbyshire is found in thick nodular beds or "floors" in spheroidal masses known as "balls" or "bowls" and in smaller lenticular masses termed "cakes". At Chellaston, where

1095-538: Is as follows: In this case the calcium oxalate (CaC 2 O 4 ) formed in the reaction is washed away with the slurry, leaving a surface that has not been chemically changed. The haloalkaliphilic methylotrophic bacterium Methylophaga murata was isolated from deteriorating marble in the Kremlin . Bacterial and fungal degradation was detected in four samples of marble from Milan Cathedral ; black Cladosporium attacked dried acrylic resin using melanin. Marble

1168-470: Is commonly used for sculpture and as a building material . The word "marble" derives from the Ancient Greek μάρμαρον ( mármaron ), from μάρμαρος ( mármaros ), "crystalline rock, shining stone", perhaps from the verb μαρμαίρω ( marmaírō ), "to flash, sparkle, gleam"; R. S. P. Beekes has suggested that a " Pre-Greek origin is probable". This stem is also the ancestor of

1241-540: Is derived: onyx-marble or alabaster-onyx, or sometimes simply (and wrongly) as onyx . Egyptian alabaster has been worked extensively near Suez and Assiut . This stone variety is the "alabaster" of the ancient Egyptians and Bible and is often termed Oriental alabaster , since the early examples came from the Far East . The Greek name alabastrites is said to be derived from the town of Alabastron in Egypt , where

1314-489: Is found in a crystal, and often the stoichiometry is variable, reflected in the crystallographic concept of "partial occupancy". It is common and conventional for a chemist to "dry" a sample with a combination of vacuum and heat "to constant weight". For other solvents of crystallization, analysis is conveniently accomplished by dissolving the sample in a deuterated solvent and analyzing the sample for solvent signals by NMR spectroscopy . Single crystal X-ray crystallography

1387-406: Is home to a natural gypsum cave in which much of the gypsum is in the form of alabaster. There are several types of alabaster found at the site, including pink, white, and the rare black alabaster. Chronological list of examples: Water of crystallization In chemistry, water(s) of crystallization or water(s) of hydration are water molecules that are present inside crystals . Water

1460-519: Is known as: onyx-marble , Egyptian alabaster , and Oriental alabaster , which terms usually describe either a compact, banded travertine stone or a stalagmitic limestone colored with swirling bands of cream and brown. In general, ancient alabaster is calcite in the wider Middle East , including Egypt and Mesopotamia , while it is gypsum in medieval Europe . Modern alabaster is most likely calcite but may be either. Both are easy to work and slightly soluble in water. They have been used for making

1533-445: Is not uncommon for proteins. Knowledge of hydration is essential for calculating the masses for many compounds. The reactivity of many salt-like solids is sensitive to the presence of water. The hydration and dehydration of salts is central to the use of phase-change materials for energy storage. A salt with associated water of crystallization is known as a hydrate . The structure of hydrates can be quite elaborate, because of

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1606-455: Is often able to detect the presence of these solvents of crystallization as well. Other methods may be currently available. In the table below are indicated the number of molecules of water per metal in various salts. Examples are rare for second and third row metals. No entries exist for Mo, W, Tc, Ru, Os, Rh, Ir, Pd, Hg, Au. AuCl 3 (H 2 O) has been invoked but its crystal structure has not been reported. Transition metal sulfates form

1679-420: Is often incorporated in the formation of crystals from aqueous solutions . In some contexts, water of crystallization is the total mass of water in a substance at a given temperature and is mostly present in a definite ( stoichiometric ) ratio. Classically, "water of crystallization" refers to water that is found in the crystalline framework of a metal complex or a salt , which is not directly bonded to

1752-542: Is on display in Sir John Soane's Museum , London ; it is carved in a single block of translucent calcite alabaster from Alabastron. Algerian onyx-marble has been quarried largely in the province of Oran . Calcite alabaster was quarried in ancient Israel in the cave known as the Twins Cave near Beit Shemesh . Herod used this alabaster for baths in his palaces. In Mexico , there are famous deposits of

1825-407: Is pyramidal (mean O/Cl−Sn−O/Cl angle is 83°) being bound to two chloride ions and one water. The second water in the formula unit is hydrogen-bonded to the chloride and to the coordinated water molecule. Water of crystallization is stabilized by electrostatic attractions, consequently hydrates are common for salts that contain +2 and +3 cations as well as −2 anions. In some cases, the majority of

1898-514: Is sent to Florence for figure-sculpture, while the common kinds are carved locally, into vases, lights, and various ornamental objects. These items are objects of extensive trade, especially in Florence, Pisa , and Livorno . In the 3rd century BC the Etruscans used the alabaster of Tuscany from the area of modern-day Volterra to produce funeral urns , possibly taught by Greek artists. During

1971-749: Is the Fuentes- Azaila area, in the Tertiary Ebro Basin. The other is the Calatayud -Teruel Basin, which divides the Iberian Range in two main sectors (NW and SE). The abundance of Aragonese alabaster was crucial for its use in architecture, sculpture and decoration. There is no record of use by pre-Roman cultures, so the first ones to use alabaster from Aragon may have been the Romans, who produced vessels from alabaster following

2044-419: Is then divided by the molar mass of water to obtain the number of molecules of water bound to the salt. Water is particularly common solvent to be found in crystals because it is small and polar. But all solvents can be found in some host crystals. Water is noteworthy because it is reactive, whereas other solvents such as benzene are considered to be chemically innocuous. Occasionally more than one solvent

2117-588: The Aljafería Palace, together with other interesting elements like capitals, reliefs and inscriptions, were made using alabaster, but it was during the artistic and economic blossoming of the Renaissance that Aragonese alabaster reached its golden age. In the 16th century sculptors in Aragon chose alabaster for their best works. They were adept at exploiting its lighting qualities and generally speaking

2190-528: The British Museum , are some of the best known. Gypsum alabaster was widely used for small sculpture for indoor use in the ancient world, especially in ancient Egypt and Mesopotamia . Fine detail could be obtained in a material with an attractive finish without iron or steel tools. Alabaster was used for vessels dedicated for use in the cult of the deity Bast in the culture of the ancient Egyptians, and thousands of gypsum alabaster artifacts dating to

2263-628: The Cathedral of Our Lady of the Angels , dedicated in 2002 by the Los Angeles, California, Archdiocese . The cathedral incorporates special cooling to prevent the panes from overheating and turning opaque. The ancients used the calcite type, while the modern Los Angeles cathedral employs gypsum alabaster. There are also multiple examples of alabaster windows in ordinary village churches and monasteries in northern Spain. Calcite alabaster, harder than

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2336-579: The Ebro Valley in Aragon , Spain , which has the world's largest known exploitable deposits. According to a brochure published by the Aragon government, alabaster has elsewhere either been depleted, or its extraction is so difficult that it has almost been abandoned or is carried out at a very high cost. There are two separate sites in Aragon, both are located in Tertiary basins. The most important site

2409-574: The English word "marmoreal", meaning "marble-like." While the English term "marble" resembles the French marbre , most other European languages (with words like "marmoreal") more closely resemble the original Ancient Greek. Marble is a rock resulting from metamorphism of sedimentary carbonate rocks , most commonly limestone or dolomite . Metamorphism causes variable re-crystallization of

2482-677: The English Reformation the making of altarpiece sets was discontinued, but funerary monument work in reliefs and statues continued. In addition to the carvings still in Britain (particularly the Nottingham Castle Museum , British Museum , and Victoria and Albert Museum ), trade in mineral alabaster (other than the antiques trade) is ongoing as far afield as the Musée de Cluny , Spain, and Scandinavia. Alabaster

2555-552: The Middle Ages the craft of alabaster was almost completely forgotten. A revival started in the mid-16th century, and until the beginning of the 17th century alabaster work was strictly artistic and did not expand to form a large industry. In the 17th and 18th centuries production of artistic, high-quality Renaissance-style artifacts stopped altogether, replaced by less sophisticated, cheaper items better suited for large-scale production and commerce. The new industry prospered, but

2628-493: The dimension stone trade, the term marble is used for any crystalline calcitic rock (and some non-calcitic rocks) useful as building stone. For example, Tennessee marble is really a dense granular fossiliferous gray to pink to maroon Ordovician limestone, that geologists call the Holston Formation . Ashgabat , the capital city of Turkmenistan , was recorded in the 2013 Guinness Book of Records as having

2701-501: The 14th and 15th centuries the carving into small statues and sets of relief panels for altarpieces was a valuable local industry in Nottingham , as well as a major English export. These were usually painted, or partly painted. It was also used for the effigies, often life size, on tomb monuments , as the typical recumbent position suited the material's lack of strength, and it was cheaper and easier to work than good marble. After

2774-691: The Elder and Ptolemy wrote that the stone used for ointment jars called alabastra came from a region of Egypt known as Alabastron or Alabastrites. The purest alabaster is a snow-white material of fine uniform grain, but it often is associated with an oxide of iron , which produces brown clouding and veining in the stone. The coarser varieties of gypsum alabaster are converted by calcination into plaster of Paris , and are sometimes known as "plaster stone". The softness of alabaster enables it to be carved readily into elaborate forms, but its solubility in water renders it unsuitable for outdoor work. If alabaster with

2847-723: The Greek and Egyptian models. It seems that since the reconstruction of the Roman Wall in Zaragoza in the 3rd century AD with alabaster, the use of this material became common in building for centuries. Muslim Saraqusta (Zaragoza) was also called "Medina Albaida", the White City, due to the appearance of its alabaster walls and palaces, which stood out among gardens, groves and orchards by the Ebro and Huerva Rivers. The oldest remains in

2920-461: The degree of hydration can be critical to the resulting chemical properties. For example, anhydrous RhCl 3 is not soluble in water and is relatively useless in organometallic chemistry whereas RhCl 3 ·3H 2 O is versatile. Similarly, hydrated AlCl 3 is a poor Lewis acid and thus inactive as a catalyst for Friedel-Crafts reactions . Samples of AlCl 3 must therefore be protected from atmospheric moisture to preclude

2993-827: The evolution of alabaster use after World War II are Volterran Umberto Borgna , the "first alabaster designer", and later on the architect and industrial designer Angelo Mangiarotti . Gypsum alabaster is a common mineral, which occurs in England in the Keuper marls of the Midlands , especially at Chellaston in Derbyshire , at Fauld in Staffordshire , and near Newark in Nottinghamshire . Deposits at all of these localities have been worked extensively. In

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3066-487: The excavated material will be waste, this is often then used as chips for flooring or wall finish, and uses for which high-calcium limestone is suitable. Marble sludge waste can be used as a mineral filler in water-based paints. Using ground calcium carbonate as a filler in paint production can improve the brightness, hiding power and application performance of paint, and can also replace expensive pigments such as titanium dioxide . Recycling of marble waste leads to

3139-408: The existence of hydrogen bonds that define polymeric structures. Historically, the structures of many hydrates were unknown, and the dot in the formula of a hydrate was employed to specify the composition without indicating how the water is bound. Per IUPAC's recommendations, the middle dot is not surrounded by spaces when indicating a chemical adduct. Examples: For many salts, the exact bonding of

3212-454: The favorite medium for Greek and Roman sculptors and architects (see classical sculpture ), marble has become a cultural symbol of tradition and refined taste. Its extremely varied and colorful patterns make it a favorite decorative material. Places named after the stone include Marblehead, Massachusetts ; Marblehead, Ohio ; Marble Arch , London; the Sea of Marmara ; India's Marble Rocks ; and

3285-495: The finished art pieces retained their natural color. In modern Europe , the centre of the alabaster trade is Florence, Italy . Tuscan alabaster occurs in nodular masses embedded in limestone, interstratified with marls of Miocene and Pliocene age. The mineral is worked largely by means of underground galleries, in the district of Volterra . Several varieties are recognized—veined, spotted, clouded, agatiform, and others. The finest kind, obtained principally from Castellina ,

3358-437: The formation of "black-crust" (accumulation of calcium sulphate, nitrates and carbon particles). Vinegar and other acidic solutions should be avoided in the cleaning of marble products. Crystallization refers to a method of imparting a glossy, more durable finish on to a marble floor (CaCO 3 ). It involves polishing the surface with an acidic solution and a steel wool pad on a flooring machine. The chemical reaction below shows

3431-477: The formation of hydrates. Crystals of hydrated copper(II) sulfate consist of [Cu(H 2 O) 4 ] centers linked to SO 2− 4 ions. Copper is surrounded by six oxygen atoms, provided by two different sulfate groups and four molecules of water. A fifth water resides elsewhere in the framework but does not bind directly to copper. The cobalt chloride mentioned above occurs as [Co(H 2 O) 6 ] and Cl . In tin chloride, each Sn(II) center

3504-450: The gypsum variety, was used in ancient Egypt and the wider Middle East (except Assyrian palace reliefs ), and also in modern times. It is found as either a stalagmitic deposit from the floor and walls of limestone caverns , or as a kind of travertine , similarly deposited in springs of calcareous water. Its deposition in successive layers gives rise to the banded appearance that the marble often shows on cross-section, from which its name

3577-562: The late 4th millennium BC also have been found in Tell Brak (modern Nagar ), in Syria . In Mesopotamia, gypsum alabaster was the material of choice for figures of deities and devotees in temples, as in a figure believed to represent the deity Abu dating to the first half of the 3rd millennium BC, which is kept in New York. Much of the world's alabaster is extracted from the centre of

3650-566: The limestone. Green coloration is often due to serpentine resulting from originally magnesium-rich limestone or dolomite with silica impurities. These various impurities have been mobilized and recrystallized by the intense pressure and heat of the metamorphism. Acids react with the calcium carbonate in marble, producing carbonic acid (which decomposes quickly to CO 2 and H 2 O) and other soluble salts : Outdoor marble statues, gravestones , or other marble structures are damaged by acid rain whether by carbonation , sulfation or

3723-462: The local alabaster is known as "Patrick", it has been worked into ornaments under the name of "Derbyshire spar"―a term more properly applied to fluorspar . Black alabaster is a rare anhydrite form of the gypsum-based mineral. The black form is found in only three veins in the world, one each in United States , Italy , and China . Alabaster Caverns State Park , near Freedom, Oklahoma ,

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3796-414: The metal cation . Upon crystallization from water, or water-containing solvents , many compounds incorporate water molecules in their crystalline frameworks. Water of crystallization can generally be removed by heating a sample but the crystalline properties are often lost. Compared to inorganic salts , proteins crystallize with large amounts of water in the crystal lattice. A water content of 50%

3869-458: The metal sulfates occur in nature, being the result of weathering of mineral sulfides. Many monohydrates are known. Transition metal nitrates form a variety of hydrates. The nitrate anion often binds to the metal, especially for those salts with fewer than six aquo ligands . Nitrates are uncommon in nature, so few minerals are represented here. Hydrated ferrous nitrate has not been characterized crystallographically. Marble Marble

3942-546: The nation's GDP. The vast majority of the industry's exports are to Israel. Marble in the geologic sense does not naturally outcrop in Palestine, and that the vast majority of commercially labeled marble produced in Palestine produced would be geologically considered limestone. Particulate air pollution exposure has been found to be elevated in the marble production industry. Exposure to the dust produced by cutting marble could impair lung function or cause lung disease in workers, such as silicosis . Skin and eye problems are also

4015-421: The needed size ("squaring"), and then are processed in different techniques: turned on a lathe for round shapes, carved into three-dimensional sculptures , chiselled to produce low relief figures or decoration; and then given an elaborate finish that reveals its transparency, colour, and texture. In order to diminish the translucency of the alabaster and to produce an opacity suggestive of true marble,

4088-591: The newly developed craft, artistic work became again possible, chiefly by Volterran sculptor Albino Funaioli . After a short slump, the industry was revived again by the sale of mass-produced mannerist Expressionist sculptures. It was further enhanced in the 1920s by a new branch that created ceiling and wall lamps in the Art Deco style, culminating in participation at the 1925 International Exposition of Modern Industrial and Decorative Arts in Paris . Important names in

4161-480: The north of modern Iraq , which was used for the Assyrian palace reliefs of the 9th to 7th centuries BC; these are the largest type of alabaster sculptures to have been regularly made. The relief is very low and the carving detailed, but large rooms were lined with continuous compositions on slabs around 7 feet (2.1 m) high. The Lion Hunt of Ashurbanipal and military Lachish reliefs , both 7th century and in

4234-645: The original carbonate mineral grains. The resulting marble rock is typically composed of an interlocking mosaic of carbonate crystals . Primary sedimentary textures and structures of the original carbonate rock ( protolith ) have typically been modified or destroyed. Pure white marble is the result of metamorphism of a very pure ( silicate -poor) limestone or dolomite protolith. The characteristic swirls and veins of many colored marble varieties, sometimes called striations , are usually due to various mineral impurities such as clay , silt , sand , iron oxides , or chert which were originally present as grains or layers in

4307-497: The reduced need for skilled craftsmen left few of them still working. The 19th century brought a boom to the industry, largely due to the "traveling artisans" who offered their wares to the palaces of Europe, as well as to America and the East. In the 19th century new processing technology was also introduced, allowing for the production of custom-made, unique pieces, as well as the combination of alabaster with other materials. Apart from

4380-688: The same place and time. This was the case with small flasks of the alabastron type made in Cyprus from the Bronze Age into the Classical period. When cut into thin sheets, alabaster is translucent enough to be used for small windows. It was used for this purpose in Byzantine churches and later in medieval ones, especially in Italy . Large sheets of Aragonese gypsum alabaster are used extensively in

4453-421: The statues are immersed in a bath of water and heated gradually—nearly to the boiling point—an operation requiring great care, because if the temperature is not regulated carefully, the stone acquires a dead-white, chalky appearance. The effect of heating appears to be a partial dehydration of the gypsum. If properly treated, it very closely resembles true marble and is known as " marmo di Castellina ". Alabaster

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4526-409: The stone before being scattered out, resulting in the characteristic waxy look which brings a lifelike luster to marble sculptures of any kind, which is why many sculptors preferred and still prefer marble for sculpting the human form. Construction marble is a stone which is composed of calcite, dolomite or serpentine that is capable of taking a polish. More generally in construction , specifically

4599-480: The stone was quarried. The locality may owe its name to the mineral; though the origin of the mineral name is obscure The "Oriental" alabaster was highly esteemed for making small perfume bottles or ointment vases called alabastra ; the vessel name has been suggested as a possible source of the mineral name. In Egypt, craftsmen used alabaster for canopic jars and various other sacred and sepulchral objects. The sarcophagus of Seti I , found in his tomb near Thebes ,

4672-616: The towns of Marble, Minnesota ; Marble, Colorado ; Marble Falls, Texas , and Marble Hill, Manhattan, New York . The Elgin Marbles are marble sculptures from the Parthenon in Athens that are on display in the British Museum . Total world quarrying production in 2019 was approximately 316 million tonnes; however, quarrying waste accounted for 53% of this total production. In the process of marble mining and processing, around half or

4745-420: The water is unimportant because the water molecules are made labile upon dissolution. For example, an aqueous solution prepared from CuSO 4 ·5H 2 O and anhydrous CuSO 4 behave identically. Therefore, knowledge of the degree of hydration is important only for determining the equivalent weight : one mole of CuSO 4 ·5H 2 O weighs more than one mole of CuSO 4 . In some cases,

4818-433: The water molecules in the crystal are not directly bonded to Ni , and these might be termed "water of crystallization". The water content of most compounds can be determined with a knowledge of its formula. An unknown sample can be determined through thermogravimetric analysis (TGA) where the sample is heated strongly, and the accurate weight of a sample is plotted against the temperature. The amount of water driven off

4891-506: The weight of a compound arises from water. Glauber's salt , Na 2 SO 4 (H 2 O) 10 , is a white crystalline solid with greater than 50% water by weight. Consider the case of nickel(II) chloride hexahydrate. This species has the formula NiCl 2 (H 2 O) 6 . Crystallographic analysis reveals that the solid consists of [ trans - NiCl 2 (H 2 O) 4 ] subunits that are hydrogen bonded to each other as well as two additional molecules of H 2 O . Thus one third of

4964-655: The widespread exchange of marble objects, including building elements, sculptures, and sarcophagi . There was a significant increase in the distribution of white marble from the late 1st century BC to the end of the 2nd century AD. A gradual decline in distribution started in the third century AD. According to the United States Geological Survey , U.S. domestic marble production in 2006 was 46,400 tons valued at about $ 18.1 million, compared to 72,300 tons valued at $ 18.9 million in 2005. Crushed marble production (for aggregate and industrial uses) in 2006

5037-415: The world's highest concentration of white marble buildings. The extraction of marble is performed by quarrying . Blocks are favoured for most purposes, and can be created through various techniques, including drilling and blasting, water jet and wedge methods. Limestones are often commercially and historically referred to as marble, which differs from the geological definition. In 1998, marble production

5110-753: Was China with a 64% market share, followed by India with 11% and Italy with 5%. White marbles throughout the Mediterranean basin were widely utilized during the Roman period. Extraction centers were unevenly distributed across the Italian Peninsula , mainland Greece , the Aegean Islands , Asia Minor , and smaller hubs like those in the Iberian Peninsula . The need for extensive trade arose due to this imbalance, leading to

5183-465: Was 11.8 million tons valued at $ 116 million, of which 6.5 million tons was finely ground calcium carbonate and the rest was construction aggregate . For comparison, 2005 crushed marble production was 7.76 million tons valued at $ 58.7 million, of which 4.8 million tons was finely ground calcium carbonate and the rest was construction aggregate. U.S. dimension marble demand is about 1.3 million tons. The DSAN World Demand for (finished) Marble Index has shown

5256-564: Was borrowed from Old French alabastre , in turn derived from Latin alabaster , and that from Greek ἀλάβαστρος ( alábastros ) or ἀλάβαστος ( alábastos ). The Greek words denoted a vase of alabaster. The name may be derived further from ancient Egyptian a-labaste , which refers to vessels of the Egyptian goddess Bast . She was represented as a lioness and frequently depicted as such in figures placed atop these alabaster vessels. Ancient Roman authors Pliny

5329-447: Was dominated by 4 countries that accounted for almost half of world production of marble and decorative stone. Italy and China were the world leaders, each representing 16% of world production, while Spain and India produced 9% and 8%, respectively. In 2018 Turkey was the world leader in marble export, with 42% share in global marble trade, followed by Italy with 18% and Greece with 10%. The largest importer of marble in 2018

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