“Will father be there?' She asked.John turned to her in astonishment.Your father is dead,' he replied somberly. 'Why should he go to Hades? You have it confused with another place that was abolished long ago.' After supper they folded up the table-cloth and spread their blankets for the night.What a dream it was,' Kismine sighed, gazing up at the stars. 'How strange it seems to be here with one dress and a penniless fianc!Under the stars,' she repeated. 'I never noticed the stars before.
I always thought of them as great big diamonds that belonged to some one. Now they frighten me. They make me feel that it was all a dream, all my youth.' It was a dream,' said John quietly.
Diamond Is Unbreakable (Japanese: ダイヤモンドは砕けない, Hepburn: Daiyamondo wa Kudakenai, sometimes translated as Diamond Is Not Crash) is the fourth story arc of the Japanese manga series JoJo's Bizarre Adventure, written and illustrated by Hirohiko Araki.It was serialized in Weekly Shōnen Jump from 1992 to 1995, with the 174 chapters collected into eighteen tankōbon volumes.
'Everybody's youth is a dream, a form of chemical madness.' How pleasant then to be insane!' So I'm told,' said John gloomily. 'I don't know any longer.
At any rate, let us love for a while, for a year or so, you and me. That's a form of divine drunkenness that we can all try.
There are only diamonds in the whole world, diamonds and perhaps the shabby gift of disillusion. Well, I have that last and I will make the usual nothing of it.' 'Turn up your coat collar, little girl, the night's full of chill and you'll get pneumonia. His was a great sin who first invented consciousness.
Let us lose it for a few hours.' So wrapping himself in his blanket he fell off to sleep.”―F. Scott Fitzgerald.
See also:Before diamonds were discovered in Brazil in the 1700s, India was the only place where diamonds were mined. Early references to diamonds in India come from texts. The of mentions diamond trade in India.
Works dating from the 4th century BC describe the diamond as a well-known and precious stone but do not mention the details of diamond cutting. Another Indian description written in the beginning of the 3rd century describes strength, regularity, brilliance, ability to scratch metals, and good refractive properties as the desirable qualities of a diamond.
Kalkutta was an important trading center for diamonds in. Diamonds were traded to the east and west of India and were recognized by various cultures for their gemmological or industrial uses.
In his work, the writer noted diamond's ornamental uses, as well as its usefulness to because of its hardness. It is however highly doubtful that Pliny meant diamonds, and it is assumed that in fact several minerals such as, or even a mixture with were all referred to by the word 'adamas'.Diamonds eventually spread throughout the world, even though India had remained the only major source of the gemstone until diamonds were discovered in Brazil in 1725. A work from the 3rd century BC mentions: 'Foreigners wear it diamond in the belief that it can ward off evil influences'. The Chinese, who did not find diamonds in their country, initially did not use diamond as a jewel but used it as a ' cutting knife'. Diamonds reached from India.
Diamonds were also discovered in 700 in, and were used by the traders of. Modern history. Fleetwood Rawstone's 'Red Cap Party' of prospectors on Colesberg KopjeIn 1869, an even larger 83.50-carat (16.700 g; 0.5891 oz) diamond was found on the slopes of on the farm Vooruitzigt belonging to the De Beers brothers. This sparked off the famous 'New Rush' and within a month, 800 claims were cut into the hillock which were worked frenetically by two to three thousand men. As the land was lowered so the hillock became a mine—in time, the world-renowned. Following agreement by the British government on compensation to the for its competing land claims, Griqualand West was annexed to the in 1877. The.From 1871 to 1914, 50,000 miners dug the with picks and shovels, yielding 2,722 kg (6,001 lb) of, and by 1873 Kimberley was the second largest town in South Africa, having an approximate population of 40,000.The various smaller mining companies were amalgamated by British imperialist and into, and The Kimberley under.
In 1888, the two companies merged to form, which once had a monopoly over the world's diamond market. That monopoly had ended by 2005, following an antitrust lawsuit in the US (which De Beers settled without admitting wrongdoing, upon payment of a 295 million settlement), and a voluntary agreement between De Beers and the European Commission. The latter agreement had been overturned upon appeal by the Russian mining company Alrosa, but the European Court of Justice then upheld the decision and the European Commission subsequently concluded its investigation with no more action being taken against De Beers.Today, annual global rough diamond production is estimated to be about 130 million carats (26 tonnes; 29 short tons), of which 92% is cut and polished in, mostly in the city of. Some 85% of the world's rough diamonds, 50% of cut diamonds, and 40% of industrial diamonds are traded in, —the diamond center of the world. The city of Antwerp also hosts the, created in 1929 to become the first and biggest diamond bourse dedicated to rough diamonds. Antwerp's association with diamonds began in the late 15th century when a new technique to polish and shape the gems evolved in this city.
The diamond cutters of Antwerp are world renowned for their skill. More than 12,000 expert cutters and polishers are at work in the, at 380 workshops, serving 1,500 firms and 3,500 brokers and merchants.In the 21st century, the technology to produce perfect was developed. Diamonds produced by the latest technologies are visually identical to mined, naturally occurring diamonds. It is too early to assess the effect of future wide availability of gem-quality synthetic diamonds on the diamond market, although the traditional diamond industry has taken steps to try to create a distinction between diamonds dug from the ground and diamonds made in a factory, in part by downplaying the fact that diamonds from both sources are actually visually identical. Synthetics currently represent 2% of gem-quality diamond supply used for jewelry, but 98% of industrial-quality supply used for abrasive applications. Gemological characteristics The most familiar usage of diamonds today is as gemstones used for —a usage which dates back into.
The of white light into is the primary gemological characteristic of gem diamonds. In the twentieth century, have 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: carat, cut, color, and clarity. This system was developed by in 1953 as internationally recognized standard to evaluate diamonds characteristics.Most gem diamonds are traded on the wholesale market based on single values for each of the four Cs; for example knowing that a diamond is rated as 1.5 carats (300 mg), VS2 clarity, F color, excellent cut round brilliant, is enough to reasonably establish an expected price range. More detailed information from within each characteristic is used to determine actual for individual stones. Consumers who purchase individual diamonds are often advised to use the four Cs to pick the diamond that is 'right' for them.Other characteristics also influence the value and appearance of a gem diamond. These include physical characteristics such as the presence of as well as the diamond's source and which gemological institute evaluated the diamond.
Cleanliness also dramatically affects a diamond's beauty.There are two major non-profit gemological associations which grade and provide reports, (informally referred to by the term certificate or cert, which is a for many grading reports) on diamonds; while carat weight and cut angles are mathematically defined, the clarity and color are judged by the trained human eye and are therefore open to slight variance in interpretation. These associations are listed below. (GIA) was the first laboratory in America to issue modern diamond reports, and is held in high regard amongst gemologists for its consistent, conservative grading. Diamond High Council (HRD) Official certification laboratory of the Belgian diamond industry, located in.Within the last two decades, a number of for-profit gemological grading laboratories have also been established, many of them also based in Antwerp or New York. These entities serve to provide similar services as the non-profit associations above, but in a less expensive and more timely fashion. They produce certificates that are similar to those of the GIA.Carat The weight measures the mass of a diamond. One carat is defined as 200 (about 0.007 ).
The point unit—equal to one one-hundredth of a carat (0.01 carat, or 2 mg)—is commonly used for diamonds of less than one carat. All else being equal, the price per carat increases with carat weight, since larger diamonds are both rarer and more desirable for use as gemstones.The price per carat does not increase linearly with increasing size. Instead, there are sharp jumps around milestone carat weights, as demand is much higher for diamonds weighing just more than a milestone than for those weighing just less. As an example, a 0.99-carat diamond may have a significantly lower price per carat than a comparable 1.01-carat diamond, because of differences in demand.A weekly list, the is published by, CEO of Rapaport Group of New York, for different diamond cuts, clarity and weights. It is currently considered the retail price baseline. Jewelers often trade diamonds at negotiated discounts off the price (e.g., 'R −3%').In the wholesale trade of gem diamonds, carat is often used in denominating lots of diamonds for sale. For example, a buyer may place an order for 100 carats (20 g) of 0.5-carat (100 mg), D–F, VS2-SI1, excellent cut diamonds, indicating a wish to purchase 200 diamonds (100 carats (20 g) total mass) of those approximate characteristics.
Because of this, diamond prices (particularly among wholesalers and other industry professionals) are often quoted per carat, rather than per stone.Total carat weight (t.c.w.) is a phrase used to describe the total mass of diamonds or other gemstone in a piece of jewelry, when more than one gemstone is used. Diamond solitaire earrings, for example, are usually quoted in t.c.w. When placed for sale, indicating the mass of the diamonds in both earrings and not each individual diamond. Is also widely used for diamond necklaces, bracelets and other similar jewelry pieces.Clarity.
Main article:Clarity is a measure of internal defects of a diamond called inclusions. Inclusions may be crystals of a foreign material or another diamond crystal, or structural imperfections such as tiny cracks that can appear whitish or cloudy. The number, size, color, relative location, orientation, and visibility of inclusions can all affect the relative clarity of a diamond. The (GIA) and other organizations have developed systems to grade clarity, which are based on those inclusions which are visible to a trained professional when a diamond is viewed under 10× magnification.Diamonds become increasingly rare when considering higher clarity gradings.
Only about 20% of all diamonds mined have a clarity rating high enough for the diamond to be considered appropriate for use as a gemstone; the other 80% are relegated to industrial use. Of that top 20%, a significant portion contains one or more visible inclusions. Those that do not have a visible inclusion are known as 'eye-clean' and are preferred by most buyers, although visible inclusions can sometimes be hidden under the setting in a piece of jewelry.Most inclusions present in gem-quality diamonds do not affect the diamonds' performance or structural integrity. When set in jewelry, it may also be possible to hide certain inclusion behind mounting hardware such as prongs in a way that renders the defect invisible. However, large clouds can affect a diamond's ability to transmit and scatter light. Large cracks close to or breaking the surface may increase the likelihood of a fracture.Diamonds are graded by the major societies on a scale ranging from flawless to imperfect.Color.
The DiamondThe finest quality as per color grading is totally colorless, which is graded as D color diamond across the globe, meaning it is absolutely free from any color. The next grade has a very slight trace of color, which can be observed by any expert diamond valuer/grading laboratory.
However, when studded in jewellery these very light colored diamonds do not show any color or it is not possible to make out color shades. These are graded as E color or F color diamonds.Diamonds which show very little traces of color are graded as G or H color diamonds. Slightly colored diamonds are graded as I or J or K color. A diamond can be found in any color in addition to colorless.
Some of the colored diamonds, such as pink, are very rare.A chemically pure and structurally perfect diamond is perfectly transparent with no, or color. However, in reality most gem-sized natural diamonds are imperfect. The color of a diamond may be affected by chemical impurities and/or structural defects in the.
Depending on the hue and intensity of a diamond's coloration, a diamond's color can either detract from or enhance its value. For example, most white diamonds are discounted in price as a more yellow hue is detectable, while intense pink or blue diamonds (such as the ) can be dramatically more valuable.
The displays a spectacular array of naturally colored diamonds, which occur in every color of the rainbow.Most diamonds used as gemstones are basically transparent with little tint, or white diamonds. The most common impurity, replaces a small proportion of carbon atoms in a diamond's structure and causes a yellowish to brownish tint. This effect is present in almost all white diamonds; in only the rarest diamonds is the coloration from this effect undetectable. The GIA has developed a rating system for color in white diamonds, from D to Z (with D being 'colorless' and Z having a bright yellow coloration), which has been widely adopted in the industry and is universally recognized, superseding several older systems. The GIA system uses a benchmark set of natural diamonds of known color grade, along with standardized and carefully controlled lighting conditions. Diamonds with higher color grades are rarer, in higher demand, and therefore more expensive, than lower color grades.
Oddly enough, diamonds graded Z are also rare, and the bright yellow color is also highly valued. Diamonds graded D–F are considered 'colorless', G–J are considered 'near-colorless', K–M are 'slightly colored'. N–Y usually appear light yellow or brown.In contrast to yellow or brown hues, diamonds of other colors are more rare and valuable. While even a pale pink or blue hue may increase the value of a diamond, more intense coloration is usually considered more desirable and commands the highest prices. A variety of impurities and structural imperfections cause different colors in diamonds, including yellow, pink, blue, red, green, brown, and other hues. Diamonds with unusual or intense coloration are sometimes labeled 'fancy' in the diamond industry.
Intense yellow coloration is considered one of the fancy colors, and is separate from the color grades of white diamonds. Gemologists have developed rating systems for fancy colored diamonds, but they are not in common use because of the relative rarity of such diamonds. Main article:is the art and science of creating a gem-quality diamond out of mined rough. The cut of a diamond describes the manner in which a diamond has been shaped and polished from its beginning form as a rough stone to its final gem proportions. The cut of a diamond describes the quality of workmanship and the angles to which a diamond is cut. Often is confused with 'shape'.There are mathematical guidelines for the angles and length ratios at which the diamond is supposed to be cut in order to reflect the maximum amount of light.
Round brilliant diamonds, the most common, are guided by these specific guidelines, though fancy cut stones are not able to be as accurately guided by mathematical specifics.The techniques for cutting diamonds have been developed over hundreds of years, with perhaps the greatest achievements made in 1919 by and gem enthusiast. He developed the by calculating the ideal shape to return and scatter light when a diamond is viewed from above. The modern round brilliant has 57 facets (polished faces), counting 33 on the crown (the top half), and 24 on the pavilion (the lower half). The girdle is the thin middle part. The function of the crown is to refract light into various colors and the pavilion's function to reflect light back through the top of the diamond.Tolkowsky's calculations included some approximations. The 253-carat (50.6 g), at a 2001 diamond exhibition in Paris.
An uncut diamond does not show its prized optical properties.The process of shaping a rough diamond into a polished gemstone is both an art and a science. The choice of cut is often decided by the original shape of the rough stone, location of the inclusions and flaws to be eliminated, the preservation of the weight, popularity of certain shapes amongst consumers and many other considerations. The round brilliant cut is preferred when the crystal is an octahedron, as often two stones may be cut from one such crystal. Oddly shaped crystals such as macles are more likely to be cut in a fancy cut—that is, a cut other than the round brilliant—which the particular crystal shape lends itself to.Even with modern techniques, the cutting and polishing of a diamond crystal always results in a dramatic loss of weight; rarely is it less than 50%. Sometimes the cutters compromise and accept lesser proportions and symmetry in order to avoid inclusions or to preserve the carat rating. Since the per carat price of diamond shifts around key milestones (such as 1.00 carat (200 mg)), many one-carat diamonds are the result of compromising cut for carat. Some jewelry experts advise consumers to buy a 0.99-carat (198 mg) diamond for its better price or buy a 1.10-carat (220 mg) diamond for its better cut, avoiding a 1.00-carat (200 mg) diamond which is more likely to be a poorly cut stone.Light performance In the gem trade, the term light performance is used to describe how well a polished diamond will return light to the viewer.
There are three light properties which are described in relation to light performance: brilliance, fire, and scintillation. Brilliance refers to the white light reflections from the external and internal facet surfaces.
Fire refers to the spectral colors which are produced as a result of the diamond dispersing the white light. Scintillation refers to the small flashes of light that are seen when the diamond, light source or the viewer is moved. A diamond that is cut and polished to produce a high level of these qualities is said to be high in light performance.The setting diamonds are placed in also affect the performance of light through a diamond. The three most commonly used settings are: Prong, Bezel, and Channel. Prong settings are the most popular setting for diamond jewelry.
The prong setting consists of four or six 'claws' that cradle the diamond, allowing the maximum amount of light to enter from all angles, allowing the diamonds to appear larger and more brilliant. In bezel settings the diamond or gemstone is completely surrounded by a rim of metal, which can be molded into any shape to accommodate the stone. Used to set earrings, necklaces, bracelets, and rings, bezel settings can have open or closed backs, and generally can be molded to allow a lot of light to pass through. Channel settings set the stones right next to each other with no metal separating them.
This setting is mostly used in wedding and anniversary bands. The outer ridge is then worked over the edges of the stones to create a smooth exterior surface. This also protects the girdle area of the stone.Fluorescence About a third of all diamonds will glow under light, usually a blue color which may be noticeable under a or strong. According to the, who reviewed a of 26,010 natural diamonds, 65% of the diamonds in the sample had no. Of the 35% that did have fluorescence, 97% had fluorescence of which 38% had faint blue fluorescence and 62% had fluorescence that ranged from medium to very strong blue.
Other colors diamonds can fluoresce are, and but are very rare and are sometimes a combination of the colors such as. Some diamonds with 'very strong' fluorescence can have a 'milky' or 'oily' look to them, but they are also very rare and are termed 'overblues.'
Their study concluded that with the exception of 'overblues' and yellow fluorescent diamonds, fluorescence had little effect on transparency and that the strong and very strong blue fluorescent diamonds on average had better color appearance than non-fluorescent stones. Since blue is a to yellow and can appear to cancel it out, strong blue fluorescence had especially better color appearance with lower color graded diamonds that have a slight yellowish tint such as I or J color but had little effect on the more colorless D, E and F color grades. Cleaning. Main article:Cleanliness significantly affects a diamond's beauty.
A clean diamond is more brilliant and fiery than the same diamond when it is 'dirty'. Dirt or grease on the top of a diamond reduces its luster. Water, dirt, or grease on the bottom of a diamond interferes with the diamond's brilliance and fire. Even a thin film absorbs some light that could have been reflected to the viewer. Colored dye or smudges can affect the perceived color of a diamond. Historically, some jewelers' stones were misgraded because of smudges on the girdle, or dye on the culet.
Current practice is to clean a diamond thoroughly before grading its color.Maintaining a clean diamond can sometimes be difficult as jewelry settings can obstruct cleaning, and oils, grease, and other materials adhere well to a diamond. Many jewelers use cleaners. Some jewelers provide their customers with -based cleaning kits; are also popular.Symbolism and lore. 1.13-carat (226 mg) round diamond engagement ring.The origin of the custom to use diamonds in rings, and more recently, in, can be traced back to the and even the Romans. The Romans valued the diamond entirely on account of the supernatural powers they ascribed to it. Pliny wrote that a diamond baffles poison, keeps off insanity, and dispels vain fears. The medieval Italians copied these beliefs and added some to it: they called it the 'Pietra della Reconciliazione' (stone of reconciliation) because it maintained concord between husband and wife.
Main article:In some of the more politically unstable central African and west African countries, revolutionary groups have taken control of, using proceeds from diamond sales to finance their operations. Diamonds sold through this process are known as conflict diamonds or blood diamonds. Major diamond trading corporations continue to fund and fuel these conflicts by doing business with armed groups. In response to public concerns that their diamond purchases were contributing to war and in and, the, the diamond industry and diamond-trading nations introduced the in 2002, which is aimed at ensuring that conflict diamonds do not become intermixed with the diamonds not controlled by such rebel groups, by providing documentation and certification of diamond exports from producing countries to ensure that the proceeds of sale are not being 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, conflict diamonds smuggled to market continue to persist to some degree (about 2–3% of diamonds traded in 2000 were possible conflict diamonds ). Today, according to the Gemological Institute of America, 99% of the worlds' diamonds are conflict-free.
According to the 2006 book The Heartless Stone, two major flaws still hinder the effectiveness of the Kimberley Process: the relative ease of smuggling diamonds across African borders and giving phony histories, and the violent nature of diamond mining in nations that are not in a technical state of war and whose diamonds are therefore considered 'clean.' The Canadian Government has set up a body known as Canadian Diamond Code of Conduct to help authenticate Canadian diamonds.
This is a very stringent tracking system of diamonds and helps protect the 'conflict free' label of Canadian diamonds.Currently, gem production totals nearly 30 million carats (6.0 tonnes; 6.6 short tons) of cut and polished stones annually, and over 100 million carats (20 tonnes; 22 short tons) of mined diamonds are sold for industrial use each year, as are about 100 tonnes (110 short tons) of synthesized diamond. See also.Notes. Pliny in Book XXXVII, xv, 61 mentioned Germany as the best location of diamonds. Richards also discuss Pliny's reference in Book XXXVI, 54 of the stone of 'Naxos' as being adamas, and which had long been used for cutting and polishing. A chief product of Naxos has long been a high grade of amorphous corundum which was used as an abrasive. ('Theophrastus, On Stones', E Caley, J. Richards, Ohio State University, 1956, page 91).
They further discuss his referral to the adamas coming from the 'east' through Armenian traders, but they show this was actually based on an erroneous interpretation of Theophrastus. Williams (Gardner F. Williams, Diamond Mines of South Africa, New York, BF Buck Company, 1905) argues that the stone named ' adamas' by the Greek and further referred to by Pliny was most likely a sapphire, since this was a much more abundant stone, even among traders in Asia, than diamond (especially when used in the context of ' adamas' being an ornamental stone and not used in an 'industrial' context of engraving gems). Streeter argues similarly in his book (Edwin Streeter, Precious Stones and gems, London, Bell and Sons, 1898). There seems to be a consensus over a large period of time that in fact the ' adamas' was not a diamond, but mostly any type of corundum, several other minerals such as spinel were probably confused with diamonds as well; particularly because of a similarity in hardness and their availability in the Mediterranean area. (see discussion in Theophrastus).
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