What is quartz sand, how to discovered it, what is the benefit of quartz sand in the cement industry?
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Quartz is the mineral that has the best combination of durability and abundance, so much sand is quartz.  It is hard and common, so it must be a typical component of cement.
780394
Yes it has something to do with acids.\n\nLimestone is CaCO3 deposits. If you look at the acid-base reaction between an acid and CaCO3 you can see that the carbonate ion favors being protonated and because of the fact that it's protonated state is very unstable it readily becomes water and CO2 gas. \n\n2 H+ + CO3 2- ---> H2CO3 ---> H2O + CO2\n\nThese two products of the reaction are very healthy for environments. However, since this reaction doesn't occur in areas of mostly granite, these bi-products aren't produced leading to the acid having a more detrimental affect on the surrounding environment.
1062405
silica is basically sand. it is a oxide of silicon (SiO2) ie. silicon dioxide
1185112
Here is the boring wikipedia answer, there is another specific answer for California beach sand at the end:\n\nSand is an example of a class of materials called granular matter. Sand is a naturally occurring, finely divided rock, comprising particles or granules ranging in size from 0.0625 (or 1/16) to 2 millimeters. An individual particle in this range size is termed a sand grain. The next smaller size class in geology is silt: particles below 0.0625 mm down to 0.004 mm in size. The next larger size class above sand is gravel, with particles ranging from 2 mm up to 64 mm (see grain size for standards in use). Sand feels gritty when rubbed between your fingers (silt feels like flour).\n\n\nThe most common constituent of sand in inland continental settings and non-tropical coastal settings is silica (silicon dioxide), usually in the form of quartz which because of its chemical inertness and considerable hardness is quite resistant to weathering. However, the composition of sand varies according to local rock sources and conditions. The bright white sands found in tropical and subtropical coastal settings are ground-up limestone. Arkose is a sand or sandstone with considerable feldspar content which is derived from the weathering and erosion of a usually nearby granite. Some locations have sands that contain magnetite, chlorite, glauconite, or gypsum. Sands rich in magnetite are dark to black in color, as are sands derived from volcanic basalts. The chlorite-glauconite bearing sands are typically green in color, as are sands derived from basalts (lavas) with a high olivine content. The gypsum sand dunes of the White Sands National Monument in New Mexico are famous for their bright, white color. Sand deposits in some areas contain garnets and other resistant minerals, including some small gemstones.\n\nHere's another specific answer for California:\n\nBeaches vary in color according to the mineral content of the sand, which is also a clue to the origin to the eroded sediments that make up the sand supply. eroded shale cliffs create the charcoal gray beach sand at Shelter Cove in Humboldt County. North of Humboldt Bay, the coarse sands of Agate Beach are multicolored agates that have been ground and polished by the surf. Ground quartz and feldspar mineral make up the white beaches of Carmel, while a few miles to the north in Sand City, amber colored sand indicates the presence of iron mineral. Close inspection reveals that white sand beaches are mosaic of pale quartz grains, pink green or white feldspar and fleck o black mica.
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In cement companies there is not much of marketing activities. Because cement is a commodity there is no need for differentiation, unique marketing, etc. These companies are more sales oriented, that is they have strong salesforce. Personal selling and PR are the most important elements for cement companies. \nThere is not much advertising and the most effective and common branding practice is Corporate Social Responsibility initiatives and programs.
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You're probably right. It sounds like quartz to me.\n\nIf you have a college or university in town, take it there to the science dept. They will no doubt find it interesting.
14309
When people say "glass," they usually mean soda-lime glass.  That is made by mixing fluxes, soda ash (Na20) and lime (Ca0) with quartz and melting the mixture.  Soda and lime reduce the viscosity of the melt.\n\n"Fused quartz" is a glass (i.e. noncrystalline) that is made by melting quartz (or synthetic silicon dioxide) and cooling it too fast for crystals to form.  You can make fused quartz, but it is difficult to handle because it is so viscous.  Unless you need the properties of fused quartz, you would be better off to melt some glass.
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Quartz is a crystal mineral (like a diamond, but not as expensive). It has a specific property useful for keeping time. When exposed to electricity, it vibrates at a precise frequency. Those vibrations can be counted by electronic parts to count the number of seconds.\n\nQuartz is usually only used by digital watches.\n\nMechanical watches, like Rolex, use springs and gears to count the seconds (that's where the ticking sound comes from), but they are time-consuming and expensive to produce.\n\nQuartz watches can be made for a few dollars.
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Concrete---\n\n\n\nConcrete is a construction material that consists, in its most common form, of Portland cement, construction aggregate (generally gravel and sand) and water.\n\nConcrete does not solidify from drying after mixing and placement; the water reacts with the cement in a chemical process known as hydration. This water is absorbed by the cement, which hardens, bonding the other components together and eventually creating a stone-like material.\n\nConcrete is used more than any other man made material on the planet[1]. It is used to make pavements, building structures, foundations, motorways/roads, overpasses, parking structures, brick/block walls and footings for gates, fences and poles.\n\nAs of 2005 about six billion cubic meters of concrete are made each year, which equals one cubic meter for every person on Earth. Concrete powers a US$35 billion industry which employs over two million workers in the United States alone. Over 55,000 miles of freeways and highways in America are made of this material. The People's Republic of China currently consumes 40% of world cement production.\n\n\n\nFOR MORE INFO\nUSE THIS LINK--\n\nhttp://en.wikipedia.org/wiki/Concrete\n\nHOPE THIS HELPS
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Silicon Dioxide. SiO2. \n\nQuartz has the exact same composition as common window glass, except window glass is not in crystal form and quartz is crystalline. A crystal is a solid with a consistent and ordered atomic structure. \n\nThe rocks listed above CONTAIN quartz, along with a lot of other minerals, but they are not made entirely of quartz. It is not a latite, or crystalized silicon (which is a metal) or Granite, Rhyolite, Vesicular Rhyolite, or Pumice. Obsidian is silicon dioxide that is like glass- uncrystallized- but it is not quartz.
638357
Minerals are natural compounds formed through geological processes. The term "mineral" encompasses not only the material's chemical composition but also the mineral's structure. Minerals range in composition from pure elements and simple salts to very complex silicates with thousands of known forms (organic compounds are usually excluded). The study of minerals is called mineralogy.\n\nAn ore is a volume of rock containing components or minerals in a mode of occurrence which renders it valuable for mining. An ore must contain materials which are:\n\nvaluable \nin concentrations which can be profitably mined \nable to be extracted from waste rock by mineral processing techniques. \nOre deposits are mineral deposits defined as being economically recoverable. Mineral deposits may include those bodies of mineralisation which are uneconomic resources, of too low a grade or tonnage or technically impossible for extraction of the contained metal.\n\nWhat is valuable to mine is generally considered in terms of purely economic considerations. However, cultural, strategic or social goals of nations, tribes and individuals may render economically unfeasible bodies of rock valuable for extraction, for instance ochre, some clays and ornamental stones which are of religious, cultural or sentimental value to a population. Here, value is placed on the rock in non-economic terms.\n\nOre is thus an economic entity, not a physical entity. Fluctuations in commodity prices will determine what rock is considered valuable and hence ore, and what rock is not valuable and is considered waste. Similarly, the costs of extraction may fluctuate, for example with fuel costs, rendering mining unprofitable and turning ore into waste.\n\nThe grade or contained concentration of an ore mineral, or metal, as well as its form of occurrence, will directly affect the costs associated with mining the ore. The cost of extraction must thus be weighted against the contained metal value of the rock and a 'cut-off grade' used to define what is ore and what is waste.\n\nOre minerals are generally oxides, sulfides, silicates, or native metals that are not commonly concentrated in the Earth's crust. The ores must be processed to extract the metals of interest from the waste rock and from the ore minerals.\n\nOre bodies are formed by a variety of geological processes. The process of ore formation is called ore genesis.\n\nSome important ore minerals:\n\nArgentite\nBarite\nBeryl\nBornite\nCassiterite\nChalcocite\nChalcopyrite\nChromite\nCinnabar\nCobaltite\nColumbite-Tantalite or Coltan\nGalena\nGold\nHematite\nIlmenite\nMagnetite\nMolybdenite\nPentlandite\nScheelite\nSphalerite\nUraninite\nWolframite
11530
It's known as "grout".  It may feel gritty because it contains sand.
34438
Sand was not invented.  It was created naturally by waves or other force erroding pieces of quartz (a rock) and making it smaller.
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It depends on the type of cement and some other circumstances.\n\nEogenesis (early diagenesis) in sand can create sandstone in as little as a few years, or tens of years in the right environment. Sandstone may be cemented by quartz, calcite, clay minerals, gypsum, anhydrite, iron oxides, and other things. In an evaporitic environment sulphates like gypsum or anhydrite could cement sand into sandstone quite rapidly. Calcite is another cement that could precipitate by rapid evaporation.  One example of an environment where sandstone might form quite rapidly in this manner is an alluvial fan that is close to an evaporitic lake, like in Death Valley. I would suggest that similar environments exist near the Dead Sea.  \n\nHowever, most sandstone is cemented by quartz and clay minerals, and these often take high pressure and temperature to be deposited (diagenesis).  To reach higher pressures it may take many thousands of years, or even millions of years for the unconsolidated sandstone to be buried and eventually cemented. \n\nSource: Notes from Dr. Earl McBride's sedimentology classes.
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The quartz is a crystal which deforms when an electrical current is introduced. This is the opposite of how a piezo element microphone works; when sound strikes the element ( a crystal similar to quartz) the element deforms and creates an electrical impulse analogous to the vibration caused by the sound.\n\nWhen a steady current is applied to the crystal with the correct feedback circuit, the crystal oscilates at a set frequency. This is in fact how your computer keeps time as well! The entire system (whatever its processor speed is) is governed by a crystal utilizing this exact method.\n\nThe oscilations are then fractioned into larger units of time (since the crystal may oscilate at many millions of vibrations per second) and then coupled to the movement by some type of mechanical transducer.\n\nVery accurate time keeping is created this way.
856161
By unit volume, probably dry cement is heavier. Why? Because rocks are heavier than water.
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Actually there are many important and major exceptions to the examples already provided here. While it is true that many minerals form either by crystallization from a molten state, or by crystallization from solution, there are several other important methods of mineral formation. \n\nMetamorphism is the solid state change of molecular arrangement that forms many minerals without melting or dissolution. A common group of minerals often formed by metamorphism, which is the result of high (but not high enough to liquify) temperatures and/or high pressures are garnets. Other examples are  muscovite, sillimanite, biotite, kyanite, and many more.\n\nAnother example of a change in mineral composition that does not involve either dissolution or melting is the common change of anhydrite to gypsum by hydration. Anhydrite contains only CaSO4, and when H2O is chemically combined (hydrated) with anhydrite it becomes gypsum. The process can be reversed releasing the water by a change in pressure.  There are a large number of minerals that are found either in a hydrated state (chemically combined with H2O) or in a dehydrated state. Many clay minerals will change composition under pressure and heat without melting or being dissolved in water. \n\nOther minerals that are an important group are what are known as polymorphs. Polymorphs are minerals that share the same chemical composition, but have varied molecular structure. A good example of a polymorph is calcite and aragonite. Aragonite has the same chemical composition of calcite (CaCO3), but is unstable at low temperature and pressure. At a temperature of 400 degrees C, with no change in pressure, aragonite will spontaneously alter to calcite. No melting or dissolution is involved. \n\nHere's a reference for calcite/aragonite:\nhttp://www.galleries.com/minerals/carbonat/aragonit/aragonit.htm\n\nSome minerals (as in rocks) even form by biogenic processes, however the generally accepted definition of a mineral (Nickel, 1995, Canadian Mineralogist) excludes most of these from being true minerals. While these 'biominerals' may involve precipitation of the mineral from solution, the process is not straightforward precipitation as it involves a living organism. One common example is the calcite which is deposited by molluscs as part of their shells (some deposit aragonite) and many other organisms. Many bacteria play an important role in creating some biominerals. Some ore deposits of zinc sulfides are deposited by bacterial activity. See: http://www.sciencenews.org/articles/20031115/bob9.asp\nSome commercially important iron ore deposits such as banded iron formations, were deposited by the activity of cyanobacteria and contain several iron minerals. You could argue that this was simply a precipitate from a solution, but the cyanobacteria played an important role in adding the oxygen to the water that caused the iron to precipitate out. Your teeth are another example of a biogenically deposited "biomineral". Your teeth contain hydroxy apatite. Another interesting example is the biomineral equivalent of atacamite that is found in the teeth of bloodworms. This copper mineral is quite rare and the type locality for the non-biogenically formed mineral is the driest desert in the world, the Atacama of northern Chile.\nhttp://webmineral.com/data/Atacamite.shtml \nHere is the article about the bloodworm teeth:\nhttp://www.sciencenews.org/articles/20021109/note14.asp\n\nTwo other minerals that have an interesting method of formation are coesite and stishovite. These are rare dense forms of SiO2 (polymorphs of quartz) that are only found in meteorite impact craters and rarely in the kimberlite pipes where diamonds are found. These two polymorphs of quartz are formed under about 20 kilobars of pressure or more during a meteorite impact. It is hard to say if they undergo a molten state, but because they are metastable, it seems unlikely to me that they would have formed and retaine