How yellow sand is different from white. Types of sand and its scope. Is it possible to paint river sand
There is an established opinion that it is quite easy to choose sand: I ordered construction sand - here you have the raw material component for concrete and the filling for the track. But this opinion is incorrect. Since there are several varieties of sand, which have their own distinctive characteristics, and are used when performing certain tasks.
Classification
So, at the place of origin, sand is usually classified into the following types:
River sand
River sand is extracted from the bottom of rivers. It is characterized by natural purity and good culvert qualities. The size of sand grains in river sand ranges from 0.3 to 0.5 mm.
This type is used for the preparation of concrete mortars, cement screeds, sewage filters, drainage structures. It is worth noting that during the preparation of concrete mix this type of sand precipitates quickly, so the solution must be constantly mixed. The cost of river sand is from 600 to 800 rubles per 1 m 3.
Quarry sand
Quite logically, quarry sand is mined by the open method and includes impurities: dust particles, stones. Sand grains of quarry sand are much smaller than those of river sand, their sizes range from 0.6 to 3.2 mm.
In its original unprocessed form, building material can be used to arrange trenches or as a sprinkle under a foundation. Typically, leading manufacturers wash and sift open pit sand. In this case, it can be used when performing plastering and finishing works, to create an asphalt mix, to form a screed.
Sea sand
This non-metallic mineral is extracted from the bottom of the sea with the help of hydraulic shells. Foreign impurities are practically absent in it, and salt is involved in the purification.
This type of sand is considered the most popular. It is used everywhere, from the creation of concrete structures to the formation of finely divided dry mixtures. But, despite the unique characteristics of this building material, there is a shortage in it, since it is impossible to mass produce it.
Building sand is sometimes considered a separate species. But, as a rule, it means both river and quarry sand. River sand can be of two colors - yellow and gray, and quarry - brown and yellow.
But it turns out that nature also exists black sandthat glitters like metal. It can be found in different parts of the world. And this type of sand is formed as a result of geological processes.
This mineral consists of dark-colored heavy minerals and is formed by leaching of light components. The main minerals are magnetite, ilmenite, hematite.
Such sands are characterized by high radioactivity - 50-300 microroentgen per hour, but sometimes this parameter can reach a thousand microroentgen per hour. Due to its high radioactivity, this mineral is not used in construction and economic activities.
Artificial sand
It is worth noting that the above types of sand are natural, as they formed the natural destruction of rocks. But, there are also artificial sandcreated by crushing marble, limestone, granite.
The most popular among artificial types of sand is quartz. It is made by grinding and dispersing a white quartz mineral to obtain a homogeneous fraction. It differs from natural types of sand in that it does not contain impurities and has a uniform composition. These advantages allow you to accurately calculate the parameters of a structure made on quartz sand.
Depending on what kind of sand is considered, it can be said that each of them can be distinguished even visually. Mined in different places, for example, sea and river sand, will be very noticeably different in color. Sea sand is larger than river sand, and it also has completely different color schemes. Sea sand will look more gray, while river sand can be a white-yellow hue. The quarry sand contained in it large particles and impurities can also be of different colors, which helps to distinguish it visually from other types of building natural material. Characterizing quarry sand, one can easily draw attention to the fact that it will necessarily contain impurities from clay, quartz crystals and dust, which also indicates that its color can be very different. Despite the content of some unnecessary elements in it, a solution prepared precisely from quartz sand will give enormous strength and durability to the future design. There is also artificial sand, and its name alone makes it clear that the color of such a material can be completely different: from light white to the darkest. 
Most often, when a person represents summer, he has the following associations: sea, sun, beach and hot yellow sand. So soft, golden or orange, red, black, or maybe green? Colorful and unique, they are located all over the world, and some of them are truly incredible.
Beaches of all colors of the rainbow
Picturesque and colorful sandy beaches can be found in many parts of the world. According to the Guinness Book of Records, the whitest sand in the world is in Australia. Golden beaches can be found in Manduria (Italy). The individual color of each grain is influenced by minerals, rock composition, plants, and even animals living in the area. The same beach may look more yellow, gold, brown or bright orange, depending on the time of day, sun and weather.
The most beautiful and unusual beaches
The pink sands of the beach on the island of Harbor (Bahamas) look very unusual. Located on the eastern side of the island, they have this hue due to the red shells of unicellular marine animals mixed with white sand. The green Papacolea beach in Hawaii or the coast of Floreana (Galapagos Islands) looks very harmonious. If you carefully consider a handful of such sand, you can see a huge amount of glassy crystals of olive color, they make up most of the sand, as they are washed out of local rocks.
In Puerto Rico, on the island of Vieques, the red sand on the beach surprises with its beauty and unusualness. A true hidden treasure of nature is Kaihalulu Beach on the island of Maui (Hawaii). Here you can also see dark red sand. Local rocks are rich in iron, which is why such a rich shade is due. Getting here is not easy, as this picturesque place is extremely isolated and inaccessible.
What is sand?
Sand is a loose granular material covering the beaches, riverbeds and deserts of the world. It consists of different materials, varying by location. The most common sand component is silica in the form of quartz, as well as rocks and minerals such as feldspar and mica. Thanks to the weathering processes (wind, rain, thawing, freezing), all these rocks and minerals are gradually crushed and transformed into small grains.
Tropical islands, such as Hawaiian, do not have rich sources of quartz, so the sand is different in these places. It can be white due to the presence of calcium carbonate obtained from shells and skeletons of marine organisms. Tropical beaches can also have black sand, which consists of dark volcanic glass. Surprisingly little is known about the origin of sand in the world's largest deserts. Studies show that the Sahara desert was once lush in vegetation before climate change turned it into a desert.
So different sand
Why is sand in different parts of the world so different in color? Nature never ceases to amaze everyone with its diversity, including also extremely colorful sandy beaches, painted with rainbow shades: green, red, orange, pink, purple, brown, golden yellow and white. And on some beaches - black sand. So what is the reason for the difference? The answer lies in the depths of the geology of the entire coastline. Sand is fragments of rocks and minerals such as quartz and iron, the size of which varies from 63 microns (one thousandth of a millimeter) to two millimeters.
Sand in terms of geology
The geology of the surrounding areas greatly affects the composition and color of the sand. For example, on the coast, consisting of a rock formed by volcanic eruptions (granites), the sand will be lighter. If most of the coast contains metamorphic rocks that have undergone folding and mixing with other rocks, which allowed them to increase the amount of oxides such as iron, then the shades will be much more saturated.
When various rocks break up into grains, which make up sand on the beach, their color is mainly determined by the presence or absence of iron, a very common mineral on Earth. When iron minerals are exposed to air, they begin to oxidize and produce red, orange, or yellow sand. Sometimes color depends not only on geological rocks. It is affected by organisms living in water. Some beaches consist of tiny fragments of coral and skeletal remains of sea creatures such as mollusks, crustaceans and foraminifera, which give the sand a pearly white hue.
Creation and color of the beach
Beaches can form anywhere where the sea or ocean crashes into the mainland. For millennia, waves erode the coastline, creating flat spaces called beaches. These new open spaces begin to accumulate deposits falling down from the surrounding hills, as well as eroded, ejected by the waves, soil remains from the ocean floor. Coastal winds and storms also contribute to the creation of beaches. The color of the sand at any particular place usually reflects the surrounding landscape and the shades of the adjacent ocean floor.
Due to its unique geology, Hawaii has so many colored beaches that you will not find anywhere else in the world. For example, the coal-black sand of Punaluu Beach is the result of volcanic activity. It includes basalt crumbs and is considered the blackest in the world. The white sand of Hyams beach is called the whitest and cleanest in the world. It is so ground that it resembles powdered sugar. Situated on the Hawaiian island of Maui, Kaihalulu Beach is famous for being one of the few places in the world to have iron-rich red sand.
Is a black sand beach a rarity or a common occurrence?
The most unusual beaches are black sand, which is simply a stunning result of volcanic activity near the coast. Black sand can be seen on top of quartz in regions with high earthly activity, on the slopes of volcanoes and in areas where most rocks are dark in color and poor in silica. Most of them are rich in iron, and by weight this sand is heavier than ordinary quartz. Why is sand black? It may consist of a certain number of different dark minerals of volcanic nature.
Places where there is a black sand beach are often the source of deposits of precious stones such as garnets, rubies, sapphires, topazes and, of course, diamonds that form in the vicinity of volcanoes and can erupt outward along with lava flows. Black sand beaches can be found in Argentina, the South Pacific, Tahiti, the Philippines, California, Greece, the Antilles, and Hawaii.
The world is full of beautiful beaches, and there is no doubt about it. And although most people would gladly agree to soak up the bright sun, lying on the snow-white or golden sand, it is nevertheless worth paying attention to other beaches, with sands of different colors of the rainbow.
Sand is a loose loose mixture consisting of small grains that are formed due to the natural destruction of rocks. widely used in construction and industry. It has various technical characteristics, primarily due to its origin.
Some features of sand
Raw sand is mined mainly in quarries. Such material has a high content of clay particles and other impurities, so it is suitable only for sprinkling under the foundation of construction sites.
Sand treated with a large amount of water is called “alluvial”. It contains a minimum amount of impurities. Such sand has completely different technical characteristics. It is used for masonry, in plastering, for the construction of the foundation. It also produces paving slabs and concrete products.
Types of sand and their main characteristics
There are three types of sand according to the place and method of extraction:
Most often, quarry sand is yellow and gray-yellow. Clay and other substances are removed from it in two ways - washing and sifting. Sifted sand is somewhat inferior in quality to washed sand, since there are more impurities in it. For this reason, seeded sand is not used for the production of concrete products, which may crack as a result of exposure to low temperature.
River sand taken from different rivers, as a rule, has its own shade and can be yellow, brownish, gray or light gray. Less common is white river sand. Nature itself through natural washing with water made sure that its composition contained clay and other particles in a minimum amount. Such sand has a very wide scope and is a universal material. It is used in the manufacture of artificial stone, concrete and sand concrete, paving slabs.
Quartz sand owes its origin to the crushing and destruction of natural quartz. This is a milky white material, however it can be easily painted in any other color. Quartz sand has a uniform composition and is harder, unlike other types of sand, a substance. It is also distinguished by the ability of sorption and chemical inertness. In addition to construction, this material is used in the manufacture of glass, in the operation of water treatment facilities.
The color of the sand depends on the predominance of a particular mineral in its composition and can be white, light gray (quartz sand), green, greenish-gray (glauconite-quartz), pink, pinkish-gray (arkose), gray, dark -gray, greenish (graywack sand), brown of various intensities and various shades (other polymictic sands).
Conditions of education and location. Sands occur in the form of layers and lenses among other sedimentary rocks and are the products of physical and chemical weathering of various rocks, prolonged and repeated washing and sorting of clastic material by flowing waters or sea surf and sedimentation at the bottom of reservoirs. Polymict species are ubiquitous. deposits of oligomictic (quartz) sands are in the Leningrad region. (Sablinskoye on the Tosne River, Kolchanovskoye on the Syasa River, in the upper reaches of the Luga River and in the vicinity of the Luga Mountain), on Valdai, in the Bryansk Region, in many districts of the Voronezh (Latnetsk), Kursk and Moscow Regions , in the Donbass (Chasov-Yarskoye), in the North. Caucasus (Kayal), in the Urals (Kaslinsky and Magnitogorsk districts), in the East. Siberia (Tulunskoe), etc.
Diagnostics. Varieties of sand are determined by the mineral composition of debris grains. To clean their surface from films of iron hydroxides and other secondary products, it is recommended to wash sand in water and dilute hydrochloric acid.
Practical value. Essentially quartz sands are used as raw materials for the glass industry, in the production of sand filters, silicate bricks, cement mortars, plaster, as well as carborundum (a highly hard compound of silicon and carbon) and ferrosilicon (an alloy of silicon with iron); as an abrasive material in sandblasting machines and for cutting monoliths of rocks of low and medium hardness (limestone, marble, etc.); as molding material in foundry. Glauconite-quartz sand contains up to 6% K20 and is a valuable potash fertilizer. Polymict sands are widely used in road construction. Alluvial deposits of gold, platinum, diamonds, cassiterite, columbite, etc. are associated with river sand deposits. Alluvial deposits of ilmenite, magnetite, zircon, rutile, etc. are associated with ancient and modern "sea sands."
Loess
The name is from him. Loss - a cliff, in connection with the ability of the rock to form specific relief forms - stable steep cliffs, deep canyons with vertical walls. A synonym is silt, (from the Greek. A ^ supov - flour).
Characteristic signs. A dusty rock (fine earth), consisting of debris particles indistinguishable to the naked eye with a size of 0.1-0.05 mm. Non-laminated. Lightweight, porous. Light yellow or light brown. Very soft, easily rubbed with fingers into a fine powder; however, the presence of grains of sand is not felt. Dry to the touch (not greasy). Under the influence of HC1 boils. Carbonated lime is concentrated in the loess in the form of curly gum - “dutiks” (hollow) or “cranes”. Sometimes shells of land mollusks, mammalian bones come across. It soaks in water.
Conditions of education and location. The result of the accumulation over many millennia of dusty material that is lifted into the air and carried over vast distances by desert winds and sandstorms in hot climates. Layered and denser loess-like loams similar to loess are formed on a much smaller scale as a result of elutriation and washing of fine-grained material with flowing water on the slopes of hills or in floodplains of rivers.
Loess is distributed over vast territories bordering the Central Asian deserts. In the southwestern and southern parts of European Russia, it lies in the form of a powerful layer directly under the soil.
Diagnostics. Easily determined by the above physical properties, behavior in water and interaction with HC1.
Practical value. The soil formed on loess has great fertility during artificial irrigation. The high porosity of the loess, its ability to absorb water and turn into a moving mass, capable of flowing (quicksand) cause great difficulties in the construction of buildings and underground structures (underground tunnels, etc.) in moistened loess soil.
RECOMMENDED LITERATURE for independent deeper familiarization with the basics of mineralogy and petrography SCIENTIFIC AND POPULAR LITERATURE Fersman AE Entertaining mineralogy. M.-L., 1953; M., 1959. Fersman A.E. Entertaining geochemistry. Ed. ...
Mineralogical Museum named after A. E. Fersman of the Academy of Sciences of the USSR. Moscow, B-71, Leninsky Prospect, 14/16. Moscow State University M.V. Lomonosov (Moscow State University). Museum of Geography; Department of Mineralogy and Petrography, Faculty of Geology. ...
E. ON RADIOACTIVITY I. Highly radioactive Gatchettolite Carnotite Otunite (otenite) Thorburnite Uraninite, Nasturan II. Weakly radioactive Columbite-tantalite Lovchorrit, rhinolite Perovskite, loparite Pyrochlore-microlite Titanium-tantalum-nnobate Zircon (zirtolite, malacon) Table of contents - Minerals ...
