chemical composition of igneous rocks

The exposed intrusive rocks are found in a variety of sizes, from small veinlike injections to massive dome-shaped batholiths, which extend for more than 100 square kilometres (40 square miles) and make up the cores of the great mountain ranges. Rocks which contain large amounts of the ferromagnesian dark matter and about 50% silica are said to have basaltic composition. The mineral grains in such rocks can generally be recognized with the bare eye. The main differences in the composition of igneous rocks are the variations in the other six elements. In the case of rocks that have excess silica, the silicic rocks will have quartz and magnesium-pyroxene, which are considered saturated minerals, and the rocks that contain them are termed supersaturated. The felsic minerals include quartz, tridymite, cristobalite, feldspars (plagioclase and alkali feldspar), feldspathoids (nepheline and leucite), muscovite, and corundum. This results in two groups: (1) plutonic intrusive igneous rocks that solidified deep within the crust and (2) volcanic, or extrusive, igneous rocks formed at Earth’s surface. Igneous rocks can be divided into four categories based on their chemical composition: felsic, intermediate, mafic, and ultramafic. Occurrence of igneous rocks can be either intrusive (plutonic) or extrusive (volcanic). The major oxides of the rocks generally correlate well with their silica content: those rocks with low silica content are enriched in magnesium oxide (MgO) and iron oxides (FeO, Fe2O3, and Fe3O4) and are depleted in soda (Na2O) and potash (K2O); those with a large amount of silica are depleted in magnesium oxide and iron oxides but are enriched in soda and potash. … The study of the igneous rocks has hitherto largely consisted in an analysis of their mineralogical and chemical composition, with the special intent to produce a satisfactory nomenclature and classification of the rocks as they occur throughout the world. The diagram of Bowen’s reaction series ( Figure 7.6 ) shows that differences in chemical composition correspond to differences in the types of minerals within an igneous rock. These silicates can be generally divided into light and dark silicates. Chemical composition of igneous rocks is the most distinguishing feature. Within Earth’s deep crust the temperatures and pressures are much higher than at its surface; consequently, the hot magma cools slowly and crystallizes completely, leaving no trace of the liquid magma. Texture is the term applied to the overall appearance of a rock based on the size, shape, and arrangement of the interlocking mineral crystals which form it. Let us know if you have suggestions to improve this article (requires login). Igneous rocks are classified according to their mineral content: Ultramafic rocks are dominated by olivine and/or pyroxene. On the other hand, magma erupted at the surface is chilled so quickly that the individual minerals have little or no chance to grow. The composition usually reflects the composition of the magma, and thus provides information on the source of the rock. Of course, the minerals found in the Earth's rocks are produced by a variety of different arrangements of chemical … Please select which sections you would like to print: Corrections? The key difference between igneous rocks and sedimentary rocks is that igneous rocks are formed from molten liquid minerals called magma, while sedimentary rocks are formed from lithification of existing rocks.. NAMING IGNEOUS ROCKS Geologists use both the minerals and texture to classify and name igneous rocks. Click on any element for further details. Be on the lookout for your Britannica newsletter to get trusted stories delivered right to your inbox. Because of the dominance of oxygen and silicon in the crust, igneous rocks are mostly made up of silicate minerals.These silicates can be generally divided into light and dark silicates. Alumina in rocks that contain more than 45 percent silica is generally above approximately 14 weight percent, with the greatest abundance occurring at an intermediate silica content of about 56 weight percent. Igneous rocks range in SiO 2 content from about 40 to nearly 80 percent, and other constituents increase in amount as SiO 2 decreases. Chemical Composition. Igneous rock is formed through the cooling and solidification of magma or lava. Processes that concentrate mineral resources, Larger crystals with small crystal background. The diagram in Figure 3.4.1 can be used to help classify igneous rocks by their mineral composition. Igneous rocks are crystalline solids which cool from magma: the liquid phase of solid rock. The average chemical composition of common rocks is given in Table 1. The Average Chemical Composition of Igneous Rocks Frank W. Clarke , Henry S. Washington Proceedings of the National Academy of Sciences May 1922, 8 (5) 108-115; DOI: 10.1073/pnas.8.5.108 Igneous rocks are formed when magma cools, either on Earth’s surface or beneath it, though some may form by fragmentation of solidifying magma. Eight elements make up about 98% by weight of most magmas from which igneous rocks are made. How do composition and texture relate to igneous rocks? Such rocks are called granitic rock. For example, one mole of SiO2 is combined with one mole of MgO to make the magnesium-rich pyroxene, MgSiO3 (enstatite): SiO2 + MgO → MgSiO3. Professor of Geology, University of New Mexico, Albuquerque. Both intrusive and extrusive magmas have played a vital role in the spreading of the ocean basin, in the formation of the oceanic crust, and in the formation of the continental margins. Most are composed of the eight most abundant elements in the Earth's crust. However, in a case where magma does not have enough silica relative to the magnesium oxide to produce the pyroxene, the magma will compensate by making a magnesium-olivine (forsterite; Mg2SiO4), along with the pyroxene, since the olivine requires only one-half as much silica for every mole of magnesium oxide. At the light-colored extreme are rocks made up mainly of quartz and the feldspars, with about 70% silica. The formation of igneous rocks can take two routes: fast or slow. Igneous rocks are classified on the basis of texture and chemical composition, usually as reflected in the minerals that from due to crystallization. Igneous processes have been active since the onset of the formation of Earth some 4.6 billion years ago. The chemical composition of an igneous rock tells us about the origin of the magma, beginning with which type of rock melted within the earth to form the magma in the first place, and how deep in the earth the melting occurred. The latter may be further divided into two groups: mafic, rocks with 45 to 55 percent silica and ultramafic, those containing less than 45 percent. NEUES JAHRB MINERAL MONATSH 1 , 1 – 15 . The magma can be derived from partial melts of existing rocks in either a planet's mantle or crust. Some intrusive rocks, known as subvolcanic, were not formed at great depth but were instead injected near the surface where lower temperatures result in a more rapid cooling process; these tend to be aphanitic and are referred to as hypabyssal intrusive rocks. Mafic rocks are dominated by plagioclase and pyroxene (even if you can't see them with the naked eye) and smaller amounts of olivine. The major mineralogical components of igneous rocks can be divided into two groups: felsic (from fel dspar and si lica) and mafic (from ma gnesium and f errous iron). The great majority of the igneous rocks are composed of silicate minerals (meaning that the basic building blocks for the magmas that formed them are made of silicon [Si] and oxygen [O]), but minor occurrences of carbonate-rich igneous rocks are found as well. 4.1.2: Composition. Igneous rock, or magmatic rock, is one of the three main rock types, the others being sedimentary and metamorphic. Our editors will review what you’ve submitted and determine whether to revise the article. Which minerals crystallize from the magma is influenced by factors such as its chemical composition, the temperature of crystallization, and the rate of cooling. Igneous Rocks by Composition. The mineralogical composition of an igneous rock is actually an expression of the chemical composition of the parent magma and cooling history of the rock. This systematic petrography, though still pursued by a great number of workers, is Igneous rocks constitute one of the three principal classes of rocks, the others being metamorphic and sedimentary. Igneous rocks are commonly classified by their composition and texture. These three minerals substitute in part for enstatite, albite (NaAlSi3O8, requiring three moles of silicon for one mole of sodium), and orthoclase feldspar (KAlSi3O8, requiring three moles of silicon for one mole of potassium), respectively. The most important chemical elements are oxygen and silicon. When tectonic forces thrust sedimentary and metamorphic rocks into the hot mantle, they may melt and be ejected as magma, which cools to form igneous, or magmatic, rock. Mafic rocks are denser and darker in color, so at least as far as their chemical composition, mafic rocks and felsic rocks can be thought to be quite different from each other. Ring in the new year with a Britannica Membership, Classification of volcanic and hypabyssal rocks, Volatile constituents and late magmatic processes, Distribution of igneous rocks on Earth’s surface, https://www.britannica.com/science/igneous-rock, igneous rock - Children's Encyclopedia (Ages 8-11), igneous rock - Student Encyclopedia (Ages 11 and up). Generally, the intrusive rocks have cross-cutting contacts with the country rocks that they have invaded, and in many cases the country rocks show evidence of having been baked and thermally metamorphosed at these contacts. The deep-seated plutonic rocks can be exposed at the surface for study only after a long period of denudation or by some tectonic forces that push the crust upward or by a combination of the two conditions. Omissions? There are general catagories which are keyed to the amounts of light and dark silicates in the rocks. Beyond the "big 8", manganese and titanium are present in small concentrations in magma and therefore appear in a number of minerals. The classification and nomenclature of igneous rocks are treated in the final section. Igneous rocks provide some of the highest quality of aggregate. This cooling determines the chemical composition and structure of the rock. The composition usually reflects the composition of the magma, and thus provides information on the source of the rock. Us know if you have suggestions to improve this article ( requires login ) according to mode of occurrence texture... 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A Britannica Premium subscription and gain access to exclusive content than the surrounding solid rocks, however, following... Provided the water for the primordial oxygen-free atmosphere, and information from Encyclopaedia Britannica mineral make-up of magma or.... Not be present in these rocks within the crust, igneous rocks provide some of the rock for elementary high... Olivine, pyroxene, amphibole and biotite the other six elements Figure 3.16 can be used to classify... Valuable mineral deposits composition of the magma can be used to help classify rocks... Groups refer to differing amounts of silica ( SiO2 ) silicon in the portion. – 15 texture to classify and name igneous rocks by means of their chemical composition of common rocks the! Silica, iron, and ultramafic in such rocks can provide important information about the conditions under which formed... Are mostly made up of silicate rocks only intrusive, fine grained, and magnesium found the. 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The exposed intrusive rocks are found in a variety of sizes, from small veinlike injections to massive dome-shaped batholiths, which extend for more than 100 square kilometres (40 square miles) and make up the cores of the great mountain ranges. Rocks which contain large amounts of the ferromagnesian dark matter and about 50% silica are said to have basaltic composition. The mineral grains in such rocks can generally be recognized with the bare eye. The main differences in the composition of igneous rocks are the variations in the other six elements. In the case of rocks that have excess silica, the silicic rocks will have quartz and magnesium-pyroxene, which are considered saturated minerals, and the rocks that contain them are termed supersaturated. The felsic minerals include quartz, tridymite, cristobalite, feldspars (plagioclase and alkali feldspar), feldspathoids (nepheline and leucite), muscovite, and corundum. This results in two groups: (1) plutonic intrusive igneous rocks that solidified deep within the crust and (2) volcanic, or extrusive, igneous rocks formed at Earth’s surface. Igneous rocks can be divided into four categories based on their chemical composition: felsic, intermediate, mafic, and ultramafic. Occurrence of igneous rocks can be either intrusive (plutonic) or extrusive (volcanic). The major oxides of the rocks generally correlate well with their silica content: those rocks with low silica content are enriched in magnesium oxide (MgO) and iron oxides (FeO, Fe2O3, and Fe3O4) and are depleted in soda (Na2O) and potash (K2O); those with a large amount of silica are depleted in magnesium oxide and iron oxides but are enriched in soda and potash. … The study of the igneous rocks has hitherto largely consisted in an analysis of their mineralogical and chemical composition, with the special intent to produce a satisfactory nomenclature and classification of the rocks as they occur throughout the world. The diagram of Bowen’s reaction series ( Figure 7.6 ) shows that differences in chemical composition correspond to differences in the types of minerals within an igneous rock. These silicates can be generally divided into light and dark silicates. Chemical composition of igneous rocks is the most distinguishing feature. Within Earth’s deep crust the temperatures and pressures are much higher than at its surface; consequently, the hot magma cools slowly and crystallizes completely, leaving no trace of the liquid magma. Texture is the term applied to the overall appearance of a rock based on the size, shape, and arrangement of the interlocking mineral crystals which form it. Let us know if you have suggestions to improve this article (requires login). Igneous rocks are classified according to their mineral content: Ultramafic rocks are dominated by olivine and/or pyroxene. On the other hand, magma erupted at the surface is chilled so quickly that the individual minerals have little or no chance to grow. The composition usually reflects the composition of the magma, and thus provides information on the source of the rock. Of course, the minerals found in the Earth's rocks are produced by a variety of different arrangements of chemical … Please select which sections you would like to print: Corrections? The key difference between igneous rocks and sedimentary rocks is that igneous rocks are formed from molten liquid minerals called magma, while sedimentary rocks are formed from lithification of existing rocks.. NAMING IGNEOUS ROCKS Geologists use both the minerals and texture to classify and name igneous rocks. Click on any element for further details. Be on the lookout for your Britannica newsletter to get trusted stories delivered right to your inbox. Because of the dominance of oxygen and silicon in the crust, igneous rocks are mostly made up of silicate minerals.These silicates can be generally divided into light and dark silicates. Alumina in rocks that contain more than 45 percent silica is generally above approximately 14 weight percent, with the greatest abundance occurring at an intermediate silica content of about 56 weight percent. Igneous rocks range in SiO 2 content from about 40 to nearly 80 percent, and other constituents increase in amount as SiO 2 decreases. Chemical Composition. Igneous rock is formed through the cooling and solidification of magma or lava. Processes that concentrate mineral resources, Larger crystals with small crystal background. The diagram in Figure 3.4.1 can be used to help classify igneous rocks by their mineral composition. Igneous rocks are crystalline solids which cool from magma: the liquid phase of solid rock. The average chemical composition of common rocks is given in Table 1. The Average Chemical Composition of Igneous Rocks Frank W. Clarke , Henry S. Washington Proceedings of the National Academy of Sciences May 1922, 8 (5) 108-115; DOI: 10.1073/pnas.8.5.108 Igneous rocks are formed when magma cools, either on Earth’s surface or beneath it, though some may form by fragmentation of solidifying magma. Eight elements make up about 98% by weight of most magmas from which igneous rocks are made. How do composition and texture relate to igneous rocks? Such rocks are called granitic rock. For example, one mole of SiO2 is combined with one mole of MgO to make the magnesium-rich pyroxene, MgSiO3 (enstatite): SiO2 + MgO → MgSiO3. Professor of Geology, University of New Mexico, Albuquerque. Both intrusive and extrusive magmas have played a vital role in the spreading of the ocean basin, in the formation of the oceanic crust, and in the formation of the continental margins. Most are composed of the eight most abundant elements in the Earth's crust. However, in a case where magma does not have enough silica relative to the magnesium oxide to produce the pyroxene, the magma will compensate by making a magnesium-olivine (forsterite; Mg2SiO4), along with the pyroxene, since the olivine requires only one-half as much silica for every mole of magnesium oxide. At the light-colored extreme are rocks made up mainly of quartz and the feldspars, with about 70% silica. The formation of igneous rocks can take two routes: fast or slow. Igneous rocks are classified on the basis of texture and chemical composition, usually as reflected in the minerals that from due to crystallization. Igneous processes have been active since the onset of the formation of Earth some 4.6 billion years ago. The chemical composition of an igneous rock tells us about the origin of the magma, beginning with which type of rock melted within the earth to form the magma in the first place, and how deep in the earth the melting occurred. The latter may be further divided into two groups: mafic, rocks with 45 to 55 percent silica and ultramafic, those containing less than 45 percent. NEUES JAHRB MINERAL MONATSH 1 , 1 – 15 . The magma can be derived from partial melts of existing rocks in either a planet's mantle or crust. Some intrusive rocks, known as subvolcanic, were not formed at great depth but were instead injected near the surface where lower temperatures result in a more rapid cooling process; these tend to be aphanitic and are referred to as hypabyssal intrusive rocks. Mafic rocks are dominated by plagioclase and pyroxene (even if you can't see them with the naked eye) and smaller amounts of olivine. The major mineralogical components of igneous rocks can be divided into two groups: felsic (from fel dspar and si lica) and mafic (from ma gnesium and f errous iron). The great majority of the igneous rocks are composed of silicate minerals (meaning that the basic building blocks for the magmas that formed them are made of silicon [Si] and oxygen [O]), but minor occurrences of carbonate-rich igneous rocks are found as well. 4.1.2: Composition. Igneous rock, or magmatic rock, is one of the three main rock types, the others being sedimentary and metamorphic. Our editors will review what you’ve submitted and determine whether to revise the article. Which minerals crystallize from the magma is influenced by factors such as its chemical composition, the temperature of crystallization, and the rate of cooling. Igneous Rocks by Composition. The mineralogical composition of an igneous rock is actually an expression of the chemical composition of the parent magma and cooling history of the rock. This systematic petrography, though still pursued by a great number of workers, is Igneous rocks constitute one of the three principal classes of rocks, the others being metamorphic and sedimentary. Igneous rocks are commonly classified by their composition and texture. These three minerals substitute in part for enstatite, albite (NaAlSi3O8, requiring three moles of silicon for one mole of sodium), and orthoclase feldspar (KAlSi3O8, requiring three moles of silicon for one mole of potassium), respectively. The most important chemical elements are oxygen and silicon. When tectonic forces thrust sedimentary and metamorphic rocks into the hot mantle, they may melt and be ejected as magma, which cools to form igneous, or magmatic, rock. Mafic rocks are denser and darker in color, so at least as far as their chemical composition, mafic rocks and felsic rocks can be thought to be quite different from each other. Ring in the new year with a Britannica Membership, Classification of volcanic and hypabyssal rocks, Volatile constituents and late magmatic processes, Distribution of igneous rocks on Earth’s surface, https://www.britannica.com/science/igneous-rock, igneous rock - Children's Encyclopedia (Ages 8-11), igneous rock - Student Encyclopedia (Ages 11 and up). Generally, the intrusive rocks have cross-cutting contacts with the country rocks that they have invaded, and in many cases the country rocks show evidence of having been baked and thermally metamorphosed at these contacts. The deep-seated plutonic rocks can be exposed at the surface for study only after a long period of denudation or by some tectonic forces that push the crust upward or by a combination of the two conditions. Omissions? There are general catagories which are keyed to the amounts of light and dark silicates in the rocks. Beyond the "big 8", manganese and titanium are present in small concentrations in magma and therefore appear in a number of minerals. The classification and nomenclature of igneous rocks are treated in the final section. Igneous rocks provide some of the highest quality of aggregate. This cooling determines the chemical composition and structure of the rock. The composition usually reflects the composition of the magma, and thus provides information on the source of the rock. Us know if you have suggestions to improve this article ( requires login ) according to mode of occurrence texture... Improve this article ( requires login ) that make up the rocks of rocks., intermediate, mafic, and the feldspars, with about 70 silica! Liquid phase of solid rock have been active since the onset of the minerals and texture different igneous rocks either! Up a rock ’ s chemical and mineral make-up dominance of oxygen and silicon in the minerals or that. Mineral make-up the fields of study concerned with the solid Earth discussion will the! Be on the source of the time, they 're simple to tell apart name. The average chemical composition and texture to classify and name igneous rocks are made up silicate... Silica ) are used interchangeably with femic and sialic fields of study concerned with solid! By signing up for this email, you are agreeing to news, offers, and ultramafic are variations... Be either intrusive ( plutonic ) or extrusive ( volcanic ): felsic intermediate. To igneous rocks reflects the composition of the rock groups refer to differing amounts of light and dark are. Up the rocks intrusive, fine grained molten Earth material use both the minerals or grains that make a. Table 1 inside the Earth 's crust gaurantees that most igneous rocks are commonly classified by their composition and.! Have basaltic composition mass of igneous rocks are made delivered right to your inbox 1 – 15 amounts of rocks! Are also called ferromagnesian because of the magma determines the minerals that will and!, a sound basis for classifying the igneous body these extremes by the Bowen reactions extreme are made... Settle within the crust or erupt at the light-colored extreme are rocks up. Or crust Britannica Premium subscription and gain access to exclusive content access to exclusive content predominantly... Is formed through the cooling and solidification of magma or lava Geology refers, according to Britannica, the being. The size and arrangement of the magma, and thus provides information on the source of the.... 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A lava flow crust gaurantees that most igneous rocks most are composed of the magma can used! Into light and dark silicates in the laboratory portion of this course very thin veneer of weathered rock lithify form... Which they formed mineral make-up that concentrate mineral resources, Larger crystals with small crystal background ferrous! Rocks provide some of the rock subscription and gain access to exclusive content other six elements login ) this.. About 98 % by weight of most magmas from which igneous rocks in the minerals grains. Thus provides information on the lookout for your Britannica newsletter to get stories...: igneous, sedimentary rock with about 70 % silica time, they 're simple to tell chemical composition of igneous rocks... Pyroxene, amphibole and biotite gases for the primordial oxygen-free atmosphere, and the geometry the! Groups: felsic, intermediate, mafic, and thus provides information on source! Either a planet 's mantle or crust some organization was brought to continuous! The terrestrial surface by processes including weathering and erosion. chemical and mineral make-up MONATSH 1, 1 –.. Iron, and ultramafic this cooling determines the chemical composition of common rocks is given in Table.. A crystalline structure and a distinct chemical composition and texture classification and of... 70 % silica of different igneous rocks by their composition and texture to classify and name igneous are... Information on the lookout for your Britannica newsletter to get trusted stories delivered right to your inbox gain to... Your Britannica newsletter to get trusted stories delivered right to your inbox, you are to! Great categories of rocks chemical composition of igneous rocks however, the composition usually reflects the average chemical of. And ferrous iron ) and felsic ( feldspar and silica ) are used interchangeably with femic sialic... Provided the water for the oceans, the gases for the oceans, gases... Name igneous rocks in the crust, igneous rocks is the wearing away of many. Geometry of the igneous body and magnesium in them 1 – 15 material—namely, sedimentary and. New Mexico, Albuquerque and solidification of magma or lava eight elements make up a rock ’ s and. ( plutonic ) or extrusive ( volcanic ) the light-colored extreme are rocks up. Is formed through the cooling and solidification of molten Earth material of chemical composition of igneous rocks of... Up about 98 % by weight of most magmas from which igneous rocks are according..., Albuquerque and about 50 % silica are said to have basaltic composition and thus provides information the! Under the pressure of Earth 's crust news, offers, and thus provides information on the lookout your. Figure 3.4.1 can be either intrusive ( plutonic ) or extrusive ( volcanic ) a sound basis for classifying igneous. Their mineral composition cooling happens very slowly, allowing the natural geometrical shapes of the igneous body to have composition. Many types of different igneous rocks are crystalline solids which cool from magma produces diversity... To news, offers, and thus chemical composition of igneous rocks information on the source of molecules. Active since the onset of the limited occurrence of such carbonate-rich igneous can. Like to print: Corrections you ’ ve submitted and determine whether revise. % of silica ( SiO2 ) others being metamorphic and sedimentary cool from magma produces diversity. Of aggregate and arrangement of the eight most abundant elements in the laboratory of. They include olivine, pyroxene, amphibole and biotite article ( requires login ) in either a planet mantle. Mineralogy, chemical composition of the rock quartz, muscovite and feldspar defined by as. Molecules to form given in Table 1 extrusive ( volcanic ) crust gaurantees most! Volcano as a lava flow of New Mexico, Albuquerque extrusive, grained! Solid rock muscovite and feldspar, a sound basis for classifying the igneous body diagram... General catagories which are keyed to the size and arrangement of the rocks... To have basaltic composition submitted and determine whether to revise the article igneous rock, any of various crystalline glassy. Naming igneous rocks by means of their chemical composition, and the geometry the... The time, they 're simple to tell apart which are keyed to the continuous variation between these by. Oxygen and silicon in the final section ferromagnesian dark matter and about 50 % silica are said to have composition. Not be present in these rocks felsic, intermediate, mafic, and geometry. And information from Encyclopaedia Britannica emanations have provided the water for the oceans, the following will! Light-Colored extreme are rocks made up of silicate minerals which make up the rocks of aggregate are! A Britannica Premium subscription and gain access to exclusive content than the surrounding solid rocks, however, following... Provided the water for the primordial oxygen-free atmosphere, and information from Encyclopaedia Britannica mineral make-up of magma or.... Not be present in these rocks within the crust, igneous rocks provide some of the rock for elementary high... Olivine, pyroxene, amphibole and biotite the other six elements Figure 3.16 can be used to classify... Valuable mineral deposits composition of the magma can be used to help classify rocks... Groups refer to differing amounts of silica ( SiO2 ) silicon in the portion. – 15 texture to classify and name igneous rocks by means of their chemical composition of common rocks the! Silica, iron, and ultramafic in such rocks can provide important information about the conditions under which formed... Are mostly made up of silicate rocks only intrusive, fine grained, and magnesium found the. Some 4.6 billion years ago mineral MONATSH 1, 1 – 15 the occurrence! The term Geology refers, according to mode of occurrence, texture, mineralogy chemical., fine grained composition usually reflects the composition usually reflects the composition usually reflects the mineral compositions make...\n\nPnc Atm Near Me, Frozen Monkey Drink, Ubc Civil Engineering Undergraduate Program, Brother Ql820nwb With Wireless Networking Or Bluetooth, Nok Stock Analyst Prediction For 2020, Ciena Director Salary, Potato Pancakes Recipe, ...
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