Diamonds by CHRISTIAN • gr. Auswahl • versandkostenfrei • auf Rechnung • 0% Ratenzahlung» Jetzt online kaufen, später bezahlen! Ausgesuchten Diamantschmuck mit zeitlosen Designs und auch farbigen Diamanten höchster Reinheit finden Sie bei Diamond Collection. Online auf. DIAMOND ist ein führender Hersteller und Konfektionär von hochpräzisen Glasfaser-Lösungen. Die LWL-Stecker mit Kern-Kern-Zentrierung sind auch für.
Diamonds by CHRISTIANDiamonds (‚Diamanten') bezeichnet: Diamonds (Antigua), Ort im St. Philips Parish, auf der Karibikinsel Antigua. Diamonds (Film), US-amerikanischer Spielfilm. DIAMOND ist ein führender Hersteller und Konfektionär von hochpräzisen Glasfaser-Lösungen. Die LWL-Stecker mit Kern-Kern-Zentrierung sind auch für. Diamanten kaufen Sie sicher und seriös beim deutschen Diamantexperten FREIHERR DIAMONDS. Wir bieten lupenreine Diamanten als Wertanlage.
Dimonds Navigation menu VideoRihanna - Diamonds
Kimberlites can be found in narrow 1 to 4 meters dikes and sills, and in pipes with diameters that range from about 75 m to 1. Fresh rock is dark bluish green to greenish gray, but after exposure rapidly turns brown and crumbles.
They are a mixture of xenocrysts and xenoliths minerals and rocks carried up from the lower crust and mantle , pieces of surface rock, altered minerals such as serpentine , and new minerals that crystallized during the eruption.
The texture varies with depth. The composition forms a continuum with carbonatites , but the latter have too much oxygen for carbon to exist in a pure form.
Instead, it is locked up in the mineral calcite Ca C O 3. All three of the diamond-bearing rocks kimberlite, lamproite and lamprophyre lack certain minerals melilite and kalsilite that are incompatible with diamond formation.
In kimberlite, olivine is large and conspicuous, while lamproite has Ti- phlogopite and lamprophyre has biotite and amphibole.
They are all derived from magma types that erupt rapidly from small amounts of melt, are rich in volatiles and magnesium oxide , and are less oxidizing than more common mantle melts such as basalt.
These characteristics allow the melts to carry diamonds to the surface before they dissolve. Kimberlite pipes can be difficult to find.
They weather quickly within a few years after exposure and tend to have lower topographic relief than surrounding rock. If they are visible in outcrops, the diamonds are never visible because they are so rare.
In any case, kimberlites are often covered with vegetation, sediments, soils or lakes. In modern searches, geophysical methods such as aeromagnetic surveys , electrical resistivity and gravimetry , help identify promising regions to explore.
This is aided by isotopic dating and modeling of the geological history. Then surveyors must go to the area and collect samples, looking for kimberlite fragments or indicator minerals.
The latter have compositions that reflect the conditions where diamonds form, such as extreme melt depletion or high pressures in eclogites.
However, indicator minerals can be misleading; a better approach is geothermobarometry , where the compositions of minerals are analyzed as if they were in equilibrium with mantle minerals.
Finding kimberlites requires persistence, and only a small fraction contain diamonds that are commercially viable. The only major discoveries since about have been in Canada.
Since existing mines have lifetimes of as little as 25 years, there could be a shortage of new diamonds in the future.
Diamonds are dated by analyzing inclusions using the decay of radioactive isotopes. Depending on the elemental abundances, one can look at the decay of rubidium to strontium , samarium to neodymium , uranium to lead , argon to argon , or rhenium to osmium.
Those found in kimberlites have ages ranging from 1 to 3. The kimberlites themselves are much younger. Most of them have ages between tens of millions and million years old, although there are some older exceptions Argyle, Premier and Wawa.
Thus, the kimberlites formed independently of the diamonds and served only to transport them to the surface. The reason for the lack of older kimberlites is unknown, but it suggests there was some change in mantle chemistry or tectonics.
No kimberlite has erupted in human history. Such depths occur below cratons in mantle keels , the thickest part of the lithosphere.
These regions have high enough pressure and temperature to allow diamonds to form and they are not convecting, so diamonds can be stored for billions of years until a kimberlite eruption samples them.
Host rocks in a mantle keel include harzburgite and lherzolite , two type of peridotite. The most dominant rock type in the upper mantle , peridotite is an igneous rock consisting mostly of the minerals olivine and pyroxene ; it is low in silica and high in magnesium.
However, diamonds in peridotite rarely survive the trip to the surface. They formed in eclogite but are distinguished from diamonds of shallower origin by inclusions of majorite a form of garnet with excess silicon.
Diamond is thermodynamically stable at high pressures and temperatures, with the phase transition from graphite occurring at greater temperatures as the pressure increases.
Thus, the deeper origin of some diamonds may reflect unusual growth environments. In the first known natural samples of a phase of ice called Ice VII were found as inclusions in diamond samples.
The mantle has roughly one billion gigatonnes of carbon for comparison, the atmosphere-ocean system has about 44, gigatonnes. It can also be altered by surface processes like photosynthesis.
This variability implies that they are not formed from carbon that is primordial having resided in the mantle since the Earth formed.
Instead, they are the result of tectonic processes, although given the ages of diamonds not necessarily the same tectonic processes that act in the present.
Diamonds in the mantle form through a metasomatic process where a C-O-H-N-S fluid or melt dissolves minerals in a rock and replaces them with new minerals.
Diamonds form from this fluid either by reduction of oxidized carbon e. Using probes such as polarized light, photoluminescence and cathodoluminescence , a series of growth zones can be identified in diamonds.
The characteristic pattern in diamonds from the lithosphere involves a nearly concentric series of zones with very thin oscillations in luminescence and alternating episodes where the carbon is resorbed by the fluid and then grown again.
Diamonds from below the lithosphere have a more irregular, almost polycrystalline texture, reflecting the higher temperatures and pressures as well as the transport of the diamonds by convection.
Geological evidence supports a model in which kimberlite magma rises at 4—20 meters per second, creating an upward path by hydraulic fracturing of the rock.
As the pressure decreases, a vapor phase exsolves from the magma, and this helps to keep the magma fluid. Then, at lower pressures, the rock is eroded, forming a pipe and producing fragmented rock breccia.
As the eruption wanes, there is pyroclastic phase and then metamorphism and hydration produces serpentinites.
Although diamonds on Earth are rare, they are very common in space. In meteorites , about three percent of the carbon is in the form of nanodiamonds , having diameters of a few nanometers.
Sufficiently small diamonds can form in the cold of space because their lower surface energy makes them more stable than graphite.
The isotopic signatures of some nanodiamonds indicate they were formed outside the Solar System in stars. High pressure experiments predict that large quantities of diamonds condense from methane into a "diamond rain" on the ice giant planets Uranus and Neptune.
Diamonds may exist in carbon-rich stars, particularly white dwarfs. One theory for the origin of carbonado , the toughest form of diamond, is that it originated in a white dwarf or supernova.
The most familiar uses of diamonds today are as gemstones used for adornment , and as industrial abrasives for cutting hard materials.
The markets for gem-grade and industrial-grade diamonds value diamonds differently. The dispersion of white light into spectral colors is the primary gemological characteristic of gem diamonds.
In the 20th century, experts in gemology developed methods of grading diamonds and other gemstones based on the characteristics most important to their value as a gem.
Four characteristics, known informally as the four Cs , are now commonly used as the basic descriptors of diamonds: these are its mass in carats a carat being equal to 0.
A large, flawless diamond is known as a paragon. A large trade in gem-grade diamonds exists. Although most gem-grade diamonds are sold newly polished, there is a well-established market for resale of polished diamonds e.
Secondary alluvial diamond deposits, on the other hand, tend to be fragmented amongst many different operators because they can be dispersed over many hundreds of square kilometers e.
The De Beers company, as the world's largest diamond mining company, holds a dominant position in the industry, and has done so since soon after its founding in by the British businessman Cecil Rhodes.
De Beers is currently the world's largest operator of diamond production facilities mines and distribution channels for gem-quality diamonds.
As a part of reducing its influence, De Beers withdrew from purchasing diamonds on the open market in and ceased, at the end of , purchasing Russian diamonds mined by the largest Russian diamond company Alrosa.
Further down the supply chain, members of The World Federation of Diamond Bourses WFDB act as a medium for wholesale diamond exchange, trading both polished and rough diamonds.
Once purchased by Sightholders which is a trademark term referring to the companies that have a three-year supply contract with DTC , diamonds are cut and polished in preparation for sale as gemstones 'industrial' stones are regarded as a by-product of the gemstone market; they are used for abrasives.
Recently, diamond cutting centers have been established in China, India, Thailand , Namibia and Botswana. The recent expansion of this industry in India, employing low cost labor, has allowed smaller diamonds to be prepared as gems in greater quantities than was previously economically feasible.
Diamonds prepared as gemstones are sold on diamond exchanges called bourses. There are 28 registered diamond bourses in the world.
Diamonds can be sold already set in jewelry, or sold unset "loose". Mined rough diamonds are converted into gems through a multi-step process called "cutting".
Diamonds are extremely hard, but also brittle and can be split up by a single blow. Therefore, diamond cutting is traditionally considered as a delicate procedure requiring skills, scientific knowledge, tools and experience.
Its final goal is to produce a faceted jewel where the specific angles between the facets would optimize the diamond luster, that is dispersion of white light, whereas the number and area of facets would determine the weight of the final product.
For example, the diamond might be intended for display or for wear, in a ring or a necklace, singled or surrounded by other gems of certain color and shape.
Some of them are special, produced by certain companies, for example, Phoenix , Cushion , Sole Mio diamonds, etc. The most time-consuming part of the cutting is the preliminary analysis of the rough stone.
It needs to address a large number of issues, bears much responsibility, and therefore can last years in case of unique diamonds.
The following issues are considered:. After initial cutting, the diamond is shaped in numerous stages of polishing.
Unlike cutting, which is a responsible but quick operation, polishing removes material by gradual erosion and is extremely time consuming.
The associated technique is well developed; it is considered as a routine and can be performed by technicians. Those flaws are concealed through various diamond enhancement techniques, such as repolishing, crack filling, or clever arrangement of the stone in the jewelry.
Remaining non-diamond inclusions are removed through laser drilling and filling of the voids produced. And the firm created new markets in countries where no diamond tradition had existed before.
Ayer's marketing included product placement , advertising focused on the diamond product itself rather than the De Beers brand, and associations with celebrities and royalty.
Without advertising the De Beers brand, De Beers was advertising its competitors' diamond products as well,  but this was not a concern as De Beers dominated the diamond market throughout the 20th century.
De Beers still advertises diamonds, but the advertising now mostly promotes its own brands, or licensed product lines, rather than completely "generic" diamond products.
Brown-colored diamonds constituted a significant part of the diamond production, and were predominantly used for industrial purposes.
They were seen as worthless for jewelry not even being assessed on the diamond color scale. After the development of Argyle diamond mine in Australia in , and marketing, brown diamonds have become acceptable gems.
Industrial diamonds are valued mostly for their hardness and thermal conductivity, making many of the gemological characteristics of diamonds, such as the 4 Cs , irrelevant for most applications.
The boundary between gem-quality diamonds and industrial diamonds is poorly defined and partly depends on market conditions for example, if demand for polished diamonds is high, some lower-grade stones will be polished into low-quality or small gemstones rather than being sold for industrial use.
Within the category of industrial diamonds, there is a sub-category comprising the lowest-quality, mostly opaque stones, which are known as bort.
Industrial use of diamonds has historically been associated with their hardness, which makes diamond the ideal material for cutting and grinding tools.
As the hardest known naturally occurring material, diamond can be used to polish, cut, or wear away any material, including other diamonds.
Common industrial applications of this property include diamond-tipped drill bits and saws, and the use of diamond powder as an abrasive.
Less expensive industrial-grade diamonds, known as bort, with more flaws and poorer color than gems, are used for such purposes. Specialized applications include use in laboratories as containment for high-pressure experiments see diamond anvil cell , high-performance bearings , and limited use in specialized windows.
The high thermal conductivity of diamond makes it suitable as a heat sink for integrated circuits in electronics.
The mining and distribution of natural diamonds are subjects of frequent controversy such as concerns over the sale of blood diamonds or conflict diamonds by African paramilitary groups.
Only a very small fraction of the diamond ore consists of actual diamonds. The ore is crushed, during which care is required not to destroy larger diamonds, and then sorted by density.
Today, diamonds are located in the diamond-rich density fraction with the help of X-ray fluorescence , after which the final sorting steps are done by hand.
Before the use of X-rays became commonplace,  the separation was done with grease belts; diamonds have a stronger tendency to stick to grease than the other minerals in the ore.
Historically, diamonds were found only in alluvial deposits in Guntur and Krishna district of the Krishna River delta in Southern India.
Diamond extraction from primary deposits kimberlites and lamproites started in the s after the discovery of the Diamond Fields in South Africa. Most of these mines are located in Canada, Zimbabwe, Angola, and one in Russia.
In the U. The Crater of Diamonds State Park in Arkansas is open to the public, and is the only mine in the world where members of the public can dig for diamonds.
In some of the more politically unstable central African and west African countries, revolutionary groups have taken control of diamond mines , using proceeds from diamond sales to finance their operations.
Diamonds sold through this process are known as conflict diamonds or blood diamonds. In response to public concerns that their diamond purchases were contributing to war and human rights abuses in central and western Africa, the United Nations , the diamond industry and diamond-trading nations introduced the Kimberley Process in This is done by requiring diamond-producing countries to provide proof that the money they make from selling the diamonds is not used to fund criminal or revolutionary activities.
Although the Kimberley Process has been moderately successful in limiting the number of conflict diamonds entering the market, some still find their way in.
This is a stringent tracking system of diamonds and helps protect the "conflict free" label of Canadian diamonds.
Synthetic diamonds are diamonds manufactured in a laboratory, as opposed to diamonds mined from the Earth. The gemological and industrial uses of diamond have created a large demand for rough stones.
This demand has been satisfied in large part by synthetic diamonds, which have been manufactured by various processes for more than half a century.
However, in recent years it has become possible to produce gem-quality synthetic diamonds of significant size.
The majority of commercially available synthetic diamonds are yellow and are produced by so-called high-pressure high-temperature HPHT processes.
Other colors may also be reproduced such as blue, green or pink, which are a result of the addition of boron or from irradiation after synthesis.
Another popular method of growing synthetic diamond is chemical vapor deposition CVD. The growth occurs under low pressure below atmospheric pressure.
It involves feeding a mixture of gases typically 1 to 99 methane to hydrogen into a chamber and splitting them to chemically active radicals in a plasma ignited by microwaves , hot filament , arc discharge , welding torch or laser.
A diamond simulant is a non-diamond material that is used to simulate the appearance of a diamond, and may be referred to as diamante.
Cubic zirconia is the most common. The gemstone moissanite silicon carbide can be treated as a diamond simulant, though more costly to produce than cubic zirconia.
Both are produced synthetically. Diamond enhancements are specific treatments performed on natural or synthetic diamonds usually those already cut and polished into a gem , which are designed to better the gemological characteristics of the stone in one or more ways.
These include laser drilling to remove inclusions, application of sealants to fill cracks, treatments to improve a white diamond's color grade, and treatments to give fancy color to a white diamond.
Coatings are increasingly used to give a diamond simulant such as cubic zirconia a more "diamond-like" appearance.
One such substance is diamond-like carbon —an amorphous carbonaceous material that has some physical properties similar to those of the diamond.
Advertising suggests that such a coating would transfer some of these diamond-like properties to the coated stone, hence enhancing the diamond simulant.
Techniques such as Raman spectroscopy should easily identify such a treatment. Early diamond identification tests included a scratch test relying on the superior hardness of diamond.
This test is destructive, as a diamond can scratch another diamond, and is rarely used nowadays. Instead, diamond identification relies on its superior thermal conductivity.
Electronic thermal probes are widely used in the gemological centers to separate diamonds from their imitations.
These probes consist of a pair of battery-powered thermistors mounted in a fine copper tip. One thermistor functions as a heating device while the other measures the temperature of the copper tip: if the stone being tested is a diamond, it will conduct the tip's thermal energy rapidly enough to produce a measurable temperature drop.
This test takes about two to three seconds. Whereas the thermal probe can separate diamonds from most of their simulants, distinguishing between various types of diamond, for example synthetic or natural, irradiated or non-irradiated, etc.
Those techniques are also used for some diamonds simulants, such as silicon carbide, which pass the thermal conductivity test.
Optical techniques can distinguish between natural diamonds and synthetic diamonds. They can also identify the vast majority of treated natural diamonds.
Laboratories use techniques such as spectroscopy, microscopy and luminescence under shortwave ultraviolet light to determine a diamond's origin.
Several methods for identifying synthetic diamonds can be performed, depending on the method of production and the color of the diamond.
CVD diamonds can usually be identified by an orange fluorescence. Screening devices based on diamond type detection can be used to make a distinction between diamonds that are certainly natural and diamonds that are potentially synthetic.
Those potentially synthetic diamonds require more investigation in a specialized lab. Occasionally, large thefts of diamonds take place.
The gang broke through a perimeter fence and raided the cargo hold of a Swiss-bound plane. The gang have since been arrested and large amounts of cash and diamonds recovered.
The identification of stolen diamonds presents a set of difficult problems. Rough diamonds will have a distinctive shape depending on whether their source is a mine or from an alluvial environment such as a beach or river—alluvial diamonds have smoother surfaces than those that have been mined.
Determining the provenance of cut and polished stones is much more complex. The Kimberley Process was developed to monitor the trade in rough diamonds and prevent their being used to fund violence.
Before exporting, rough diamonds are certificated by the government of the country of origin. Some countries, such as Venezuela, are not party to the agreement.
The Kimberley Process does not apply to local sales of rough diamonds within a country. Diamonds may be etched by laser with marks invisible to the naked eye.
Lazare Kaplan , a US-based company, developed this method. However, whatever is marked on a diamond can readily be removed. Diamonds have been treasured as gemstones since their use as religious icons in ancient India.
Their usage in engraving tools also dates to early human history. In , the French scientist Antoine Lavoisier used a lens to concentrate the rays of the sun on a diamond in an atmosphere of oxygen , and showed that the only product of the combustion was carbon dioxide , proving that diamond is composed of carbon.
From Wikipedia, the free encyclopedia. This article is about the mineral. For the gemstone, see Diamond gemstone. Allotrope of carbon often used as a gemstone and an abrasive.
The slightly misshapen octahedral shape of this rough diamond crystal in matrix is typical of the mineral. Its lustrous faces also indicate that this crystal is from a primary deposit.
Main article: Material properties of diamond. See also: Crystallographic defects in diamond. Main article: Diamond color. Main article: Extraterrestrial diamonds.
A round brilliant cut diamond set in a ring. Main article: Diamond gemstone. Main articles: Diamond cutting and Diamond cut. JAN Garnet.
FEB Amethyst. MAR Aquamarine. APR Diamond. MAY Emerald. JUNE Pearl. JULY Ruby. AUG Peridot. SEP Sapphire.
OCT Opal. NOV Citrine. DEC Topaz. Learn About the 4Cs. Metal Education. Shine bright like a diamond Whoa-oh Shine bright like a diamond Whoa-oh Shine bright like a diamond Whoa, yeah.
Shine bright like a diamond Whoa-oh Shine bright like a diamond Whoa-oh Shine bright like a diamond Shine bright like a diamond. Please click here if you are not redirected within a few seconds.
Rihanna - Diamonds Lyrics Rihanna. Shine bright like a diamond Shine bright like a diamond Find light in the beautiful sea, I choose to be happy You and I, you and I, we're like diamonds in the sky You're a shooting star I see, a vision of ecstasy When you hold me, I'm alive, we're like diamonds in the sky I knew that we'd become one right away, oh, right away At first sight I felt the energy of sun rays I saw the life inside your eyes So shine bright tonight, you and I We're beautiful like diamonds in the sky Eye to eye, so alive We're beautiful like diamonds in the sky Related.