宝玉石学第五章_钻石

单击此处编辑母版标题样式,单击此处编辑母版文本样式,第二级,第三级,第四级,第五级,*,第五章 钻石,Chapter 5 Diamond,陈炳辉,Dr. Chen Binghui,Department of Earth Sciences,Sun Yat-sen University,Contents,概述,Introduction,世界名钻,Famous Diamonds,钻石特性,Nature of Diamonds,钻石分级评估,Diamond Grading,钻石的鉴定,Testing,钻石产地,Localities,一、概述,钻石名称的来历,钻戒作为订婚信物的来历,1477年，奥地利大公,Maximilian与法国Burgundy的玛利公主订亲时开始,上流社会对钻石的追求热潮：,1953年梦露主演君子好逑，主唱“钻石是女人最好的朋友”,钻石在宝石贸易中的地位,The name diamond comes from the Greek adamas, meaning unconquerable. Made of pure carbon, diamonds are the hardest natural substance known to man.,Diamonds were formed in the depths of the earth and are three quarters of the earths agealthough humans didnt find them until 4,000 years ago.,Under immense heat and pressure, diamonds crystallized and were brought to the earths surface through volcanic explosions of magma. This magma cooled and solidified as kimberlite ore, the primary sources where rough diamonds are still found today, in some of the most inaccessible places on the planet.,Man first discovered diamonds 4,000 years ago in the riverbeds of the Golconda region of India. These diamonds had been eroded from the primary deposits and washed into rivers. Some will have made it as far as the coast or even the seabed.,Today, most diamonds come from primary deposits. Only one fifth of all diamonds mined actually end up in jewelry.,Contents,概述,Introduction,世界名钻,Famous Diamonds,钻石特性,Nature of Diamonds,钻石分级评估,Diamond Grading,钻石的鉴定,Testing,钻石产地,Localities,World Famous Diamonds (,世界名钻),世界最大的钻石库利南,Cullinan,1905,年1月25日发现于,PREMIER,矿，3106,ct,1907,年12月9日，英国皇室,1908年初在阿姆斯特丹加工，加工费8万英镑,加工了9颗大钻石和96颗小钻石,ct,梨型,英王权杖上,ct,方型,英王冠下方正中.,The Cullinan Diamond,One of the largest diamonds ever found was in South Africa and named for the owner of the mining company. The Cullinan diamond was 3106 carats. It was cut into 105 beautiful diamonds. The largest is the,Star of Africa, a 530 carat diamond. In 1907 this diamond was given to King Edward VII of England and set into the Royal Scepter. It is kept, along with the other British Crown Jewels, in the Tower of London.,世界第二钻石“布拉冈斯”,1798年发现于巴西，1680,ct,充满血腥的钻石“沙赫”,Shah,500,多年前发现于印度，42,cm2, 99.75ct.,ct,保存在克里姆林宫,噩运之钻“希望”,HOPE,45.52ct,深蓝色,The Excelsior Diamond,A large diamond weighing 995 carats was found in 1893 by an African mine worker. The name Excelsior, meaning higher, came from the stones original shape - flat on one side and rising to a peak on the other. It was cut into 21 diamonds, the largest being 69 carats. The diamonds were sold to undisclosed parties. The Excelsior 1 was purchased in 1996 by Robert Mouawad.,The Hope Diamond,A 44 carat blue diamond set as a pendant with 16 white diamonds surrounding it and a chain of 45 white diamonds. This diamond has an infamous reputation and fluoresces with a unique reddish color when exposed to ultraviolet light. Donated to the Smithsonian.,看过泰坦尼克号的朋友们一定会记得里边的那颗海洋之心，它见证了一段美好却短暂得令人心伤的悲剧爱情故事。在现实生活中，或许海洋之心并不存在，但是，却另有一颗历史名钻，其所见证的，是许许多多的灾难。那便是希望（,Hope）。,“,希望”并未曾象其名一般，为它的拥有者带来希望，相反，却是无止尽的厄运，以至于人们另冠于它“厄运之钻”之称. 。希望的发现史已无从考证，其有着美丽的蓝色，在加工后重45.52克拉，现存于美国华盛顿史密森学院。,传说中的“希望”的流传始于约500年前。当时，一名僧侣从古印度神庙的神像头上偷得“希望”，将它卖与一商人，从此，“希望”便开始了它漫长的流浪史，而所有曾为它主人者的厄运亦从此拉开序幕。,首当其冲的，便是盗得此钻的那名僧人，在此案被破后其受绞刑而死。,1642年，法国探险家兼珠宝商人塔菲涅在印度得到它，将其带回法国。其时该钻重约112克拉。在之后的日子里，塔菲涅儿子的挥霍无度，使得原本富足的家庭负债累累，日益衰败。为重振家业，塔菲涅选择了再次远走印度，希望能觅得转机，却不幸在旅途中被野狗咬死，客死他乡。,此后，“希望”辗转流落到法国国王路易十四手中，他将这颗钻石请工匠重新琢磨至69.03克拉。然而不久，路易十四便患病死去。,随后继位的路易十五将此钻送与了他的情妇-在法国大革命中被砍了头。,之后该钻的拥有者路易十六及其王后，及王后的女友，又先后死于法国大革命中。,1792年，该钻于法国国库中失窃，在这次的流浪中，它的重量再次减小，而至今日的模样，仅剩45.52克拉。,于1830年在伦敦的珠宝市场上重新出现后，被银行家霍普（,Hope）,以18,000英镑购得，钻石从其主人名而命名，“希望”之名便从此而来。在霍普拥有“希望”的日子里，一切倒也风平浪静。当钻石传至其后人手中后，因其后代的经营不善，家境逐渐破落潦倒，最终，为偿还债务，其后人不得不变卖“希望”。此后，“希望”再次开始了它的流浪历程。,1908年，显赫一时的土耳其苏丹哈密德以40万美元的价格购得，并将其赏与其亲信左毕德。不久，左毕德便被苏丹处死，而苏丹本人亦在一年后失去王位。传说此次交易的经手商人在一次全家出门时，因车祸导致全家死于非命。,1911年，美国一邮政负责人麦克兰以11.4万美元购得“希望”作为礼物送与其妻，第二年，他们的儿子、女儿及麦克兰先生本人便先后死去。,在麦克兰夫人去世后，美国著名的珠宝商人温斯顿于1958年成为了希望的新一任主人。这次，希望终于没再给自己的历史添上悲剧的一笔，温斯顿平安地拥有着它直至最后将它捐献给史密森学院。,塞拉里昂之星（,Star of Sierra Leone）,塞拉里昂是二十世纪三十年代才发现有钻石的，该地的钻石品质佳、颗粒大并有八面体晶形。,塞拉里昂之星，重968.90克拉，是世界第三大宝石级金刚石；1972年2月14日(情人节）发现于西非塞拉里昂的科诺（,kono）,地区的河流冲积砂矿中。,塞拉里昂之星晶形不完整（故见不到八面体晶形），呈鸡蛋状，无色透明，属优质宝石级金刚石。经伦敦,DeBeers,的中央统售机构于同年6月30对其进行估价不低于100万英镑。,塞拉里昂之星被精工设计琢磨成了17块钻石，总重量为238.48克拉，占总重的24.6%，这17块钻石分别命名为,Sierra Leone-1-Sierra Leone-17，,分别琢为梨形、祖母绿形及卵形、圆钻形。,Star of Sierra Leone-2,于1988年10月在纽约钻石市场被一大富豪以352万美圆的高价买走，其重为32.52克拉，祖母绿琢形。,The Regent Diamond,Found on the Kistna River, India in 1701, this 410 carat stone originally known at the Pitt. The diamond was sold to Thomas Pitt who sent it to England to have it cut and polished. The result was a brilliant cushion shaped diamond of 140 carats. In 1717 it was sold to the the Duke of Orleans, regent of France, from which it gets the name Regent. The royals used the stone in many ways including being set in the Crown of Louis XV, as a hair ornament of Queen Marie and as an adornment in the hat of Marie Antoinette. After the French Revolution the stone was set in the hilt of Napoleon Bonapartes sword. Napoleons wife, Marie Louisa, carried the Regent back to Austria upon his death. Later her father returned it to the French Crown Jewels. Today, it remains in the French Royal Treasury at Louvre.,摄政王(,Regent),曾名“皮特”。1701年，在印度戈尔康达矿山由一名淘洗工人在淘洗金刚石的过程中发现。原重410克拉。这名工人不惜砸伤自己的脚，将这颗钻石藏于绷带中，逃离矿山。可惜后来他被见利起歹心者谋了性命。,此后，这颗钻石流落到印度商人贾姆哈德手中，他以20400英镑的价格将其卖与了英国驻印度总督威廉皮特。“皮特”之名即由此而来。,回到英国后，皮特请工匠将其琢磨成为302519,mm,的垫形钻石。经琢磨后这颗钻石的重量减少到136.9克拉。,皮特于1717年将其卖给了法国的奥尔良公爵腓力。当时法国正处于国内政局混乱时机，法国皇帝路易十五又正年幼，暂由奥尔良公爵摄政，钻石名便随主人改为了“摄政王”，被镶于路易十五的皇冠上，待其加冕时佩带。,法国大革命后，拿破仑拥有了这颗钻石，将它镶于剑柄之上。如今，摄政王如其他名钻一般，结束了被争夺的历史，静静地陈列于法国巴黎卢浮宫历史博物馆中供观赏。,The Sancy Diamond,A,55 carat diamond believed to have come from India. The pale yellow stone that fluoresces yellow and pink has become one of the most famous diamonds in history. In 1477 the diamond was lost on a field of battle by its first know owner Charles, Duke of Burgundy. Not until the 16th century was the Stancy Diamond named - for Seigneur de Sancy, a French Ambassador to Turkey.,It has been loaned to the French Kings Henry III and Henry IV, sold to the English King James I and traveled to Paris by way of James II. It has been used to raise money for war, lost for an unpaid loan, bought by a Cardinal, willed to the French Crown and stolen in a great heist of the French Crown jewels. Later it was a part of the Napoleon court, purchased by a Bombay merchant, shown at the 1867 Paris Exhibition, finally making its way in 1906 to Americas Lady Astor as a wedding tiara. In 1978, the Astor family sold the Sancy Diamond, returning it to France again. It is now housed in the Louvre.,我国现存发现的最大钻石为常林钻，是1977年12月21日，山东临沐县发山公社常林村的一位女农民在耕地时发现的，重157.77克拉，呈八面体，质地洁净、透明，淡黄色。,Contents,概述,Introduction,世界名钻,Famous Diamonds,钻石特性,Nature of Diamonds,钻石分级评估,Diamond Grading,钻石的鉴定,Testing,钻石产地,Localities,Nature of Diamond,Chemical Composition,C,，,minor elements Si, Mg, Ca, Al, Mn, N, B, Be, Fe, Ti,Diamond Classification,Type Ia: 98% Contains N (up to 2,500 ppm) as aggregates and platelets;,Type Ib: Rare in nature but most synthetic diamonds of this type N20ppm and is dispersed (non-aggregated);,Type IIa: Very rare. N 20ppm. Often very large gem diamonds;,Type IIb: Extremely rare and generally blue in color. (B 20 ppm). Most pure type of diamond.,System：Isometric,Habits,：,isometric forms such as cubes and octahedrons, twinning is also seen.,多呈八面体、菱形十二面体、立方体及其各种聚形。晶面常有生长纹及蚀象。,Crystal System and Habits,PHYSICAL CHARACTERISTICS:,Hardness is 10,Specific Gravity is 3.52 (above average),Cleavage is perfect in 4 directions forming octahedrons.,Fracture is conchoidal.,解理：具八面体111完全解理。,比重：3.473.56，一般为3.52。,硬度：10。不同晶面各方向的硬度有差异,。,Color,is variable and tends toward pale yellows, browns, grays, and also white, blue, black, reddish, greenish and colorless.,Luster,is adamantine,Transparency,crystals are transparent to,translucent in rough crystals.,refractive index,is 2.42 ( very high),dispersion,is 0.044,fluorescent,.,Associated Minerals,are limited to those found in kimberlite rock.,发光性：在紫外线长波下大多数钻石有蓝白、绿、黄、红色等荧光，少数在短波下了有荧光。有些可发磷光。在,X,射线下，大多数钻石发中-强的蓝-白色荧光。,吸收光谱：无色淡黄褐色系列钻石在415,nm,有强吸收带，423、435、465、478,nm,有弱吸收线。褐色钻石在503,nm,有强吸收线。,包裹体：常含有石墨、金刚石、铬透辉石、铬尖晶石、石榴石、橄榄石等细小矿物包体。,Contents,概述,Introduction,世界名钻,Famous Diamonds,钻石特性,Nature of Diamonds,钻石分级评估,Diamond Grading,钻石的鉴定,Testing,钻石产地,Localities,Diamond Grading,钻石评估,钻石评估四个要素 4,Cs,切工,Cut,颜色,Color,克拉重量,Carat,净度,Clarity,Cut refers to the angles and proportions a skilled craftsman creates in transforming a rough diamond into a polished diamond.,CUT,Cut,Cut is the most important factor to a diamonds beauty. Regardless of the color, clarity, and carat weight, a well-cut diamond will be beautiful.,Cut and Relation to Value,Cut quality commands a premium for two reasons. First, you are paying for a highly skilled diamond cutters time, and it can take many hours to get all the proportions and angles to fall within the Ideal or SuperIdeal ranges. Second, more of the diamond is lost in the cutting process, because the goal is not to cut the heaviest diamond, but the best performing diamond,Cut can affect the value by 25% to over 50%.,Fancy-shaped diamonds, since they retain weight from unusual shaped rough crystals, are often less expensive then comparable round diamonds.,A well-cut diamond will reflect light internally from one mirror-like facet to another, dispersing it through the top of the stone. Cuts that are too deep or too shallow lose or leak light through the side or bottom, affecting the diamonds brilliance,.,The Millennium Star, weighing 777 carats in the rough, was polished down to 203 carats in order to maximize its beauty.,切工：即钻石的切磨加工质量。,宝石最宝贵的四种光学效应,体色,亮度,火彩,闪耀程度,钻石的琢型,圆形明亮型,阶梯型,剪刀型,圆形明亮型的标准比例,Cut is the only one of the 4Cs that is influenced by the human hand. The rest (color, clarity, carat) are created naturally as diamonds form in the earth. Diamond cutting requires great skill and training. The cutter must polish tiny surfaces known as facets onto the rough diamond. This process is what creates the facets known as the crown, culet, table, girdle and pavilion of the diamond. The facets, when arranged in precise proportions, will maximize the fire life and brilliance of a diamond. To cut a diamond perfectly, a craftsman will often need to cut away more than 50% of the rough diamond,Cut also refers to the shape of a diamond: round, emerald, heart, marquise or pear for example.,A round diamond is the most brilliant of diamond shapes. Its symmetrical outline allows it to reflect nearly all of the light that enters the diamond.,Three basic types of Cutting style :,Brilliant-cuts,are scientifically found to reflect the most light.,Step-cuts,have rows of facets that resemble the steps of a staircase. The emerald and baguette are examples of this cutting style.,Mixed-cuts,have both step and brilliant-cut facets. One of the most popular types of mixed-cuts is the Princess,国际钻石委员会切工分级标准,切工评价因素：,各部分的比例和角度；,各部位的对称程度；,各面棱相交的准确度；,表面光洁度；,人工损伤情况。,切工评价方法：,肉眼检测评估；,用比例仪测量。,Color,Amount or presence of body color in a diamond.,Diamonds come in all colors.,The most rare diamond colors are red, pink, green, and blue.,The absence of color in diamonds is most rare.,Most diamonds mined in nature have traces of yellow, some brown or gray.,Color is caused in diamonds by minute traces of other elements, such as nitrogen = yellow and boron = blue.,Color is an important factor to beauty, rarity, and value because it is something a consumer can see without the aid of equipment.,Color,钻石按颜色可分为两类：,无色类：完全无色 明显浅黄（褐）色系列；,彩色类：除黄（褐）色系列外各种较鲜明的颜色。,无色类钻石以越接近完全无色品级越高。彩色类钻石则以色彩越艳丽、色调越纯正、色饱和度越高越昂贵。,钻石颜色分级主要针对无色黄色系列的钻石。,钻石颜色分级的条件：,标准比色石；标准光源；中性分级环境。,Most diamonds appear icy white, but many have tiny hints of color. Diamonds are graded on a color scale established by the Gemological Institute of America (GIA), ranging from D (colorless) to Z. Colorless diamonds are extremely rare, and therefore very valuable. But there are no hard and fast rules for what color makes a diamond beautiful.,Diamonds are also sometimes found in fancy colors: pink, blue, green, yellow, brown, orange and, very rarely, red. These diamonds, called fancies are incredibly rare and valuable. These colors extend beyond the GIA color grading system.,钻石颜色分级标准,Color Scale,Colors D, E and F are essentially without color and differ more in transparency.,Colors G, H, I and sometimes J, will usually show little or no color.,Diamond Fluorescence,A unique quality possessed by some diamonds to give off light when exposed to specific ultraviolet wavelengths. It is an unusual quality that can enhance the appearance of a diamond in certain.,Very strong fluorescence may produce an oily appearance that detracts from beauty and value.,Only 50% of all gem-quality diamonds fluoresce, and only 10% strongly fluoresce. When gem-quality diamonds fluoresce it is a bluish color.,Clarity,A a measure of the surface (blemishes) and internal (inclusions) characteristics of a polished diamond, and has, as does color, a major impact on value.,Clarity characteristics are an inherent part of a diamonds life, and can arise from events which occurred during its formation deep in the earth, the mining procedures used to collect it, the cutting of rough into its final shape and the wearing of the stone.,How Clarity is Graded,Using a 10x magnification and also the assessment of the trained unaided eye.,When a diamond is examined, the size, type, position, number, color, and relief of clarity features are observed.,钻石的净度分级,净度：指钻石含有瑕疵（缺陷）的程度，以10倍放大镜下所见为准。,瑕疵分为二类：,内部瑕疵：各种固态、液态、气态及云雾状包裹体，羽状裂隙、解理裂隙、腰棱须裂及凹角，生长线、双晶纹，激光钻孔等。,外部瑕疵：原生晶面，多余小面，抛磨痕，表面纹理（生长纹、双晶纹），粗糙腰面，划痕，缺口等。,Clarity and Price,Going from IF to VVS1 clarity will result in about a 25% decrease in price, and a further 10% decrease for each clarity grade (VVS2=-35%, VS1=-45%, VS2=-55%) until SI1 and SI2 where 5% further decreases are in order (SI1=-60%, SI2=-65%).,Clarity is a rarity factor that affects diamond value by 5 - 20% for each increment on the AGS diamond grading scale.,净度分级标准,To view inclusions, trained gemologists use a magnifying loupe. This tool allows our experts to see a diamond at 10x its actual size. Even with a loupe, the birthmarks in the VVS (Very, Very Slightly Included) to VS (Very Slightly Included) range can be very difficult to find. It is only when a diamond is graded I that it is possible to see the birthmarks with the naked eye.,Whats the difference between VVS1 and VVS2 or SI1 and SI2? The numbers represent levels within each grade. The 1s will be cleaner (have fewer or smaller inclusions) than the 2s. This allows for more precise grading categories,CARAT WEIGHT,A measurement of weight used in determining rarity in evaluating a diamond.The term Carat is derived from the ancient Carob Seed from the locust tree, used as a medium of exchange on early pan-balances. In the early 1900s the Metric Carat was established.,1 Carat = .2 Gram,There are 100 Points to a Carat.,Carats and Cuts,For well-proportioned, round diamonds a 1.00ct. stone should normally be about 6.5mm in diameter, a 3.00ct. would be 9.3mm, etc.,However, if a 1.00ct. round diamond has a shallow cut, it will look larger than a well-cut stone of the same weight because its diameter will be larger than 6.5mm.,Conversely, when a 1.00ct. round diamond is cut too deep, it appears to be of smaller size than a well-cut stone, because the diameter will be smaller than the expected 6.5mm. This means that you are paying for extra weight in the pavilion and girdle areas, which doesnt add to the beauty of the diamond.,High carat diamonds often appear to be brighter or more brilliant than their lower carat siblings due to the prism effect of light traveling over larger distances. However, carat is merely one of the factors to take into consideration when appraising the quality of the stone.,Carat Weight and Its Relation to Value,Carat weight usually has the greatest impact on value, based on rarity. Most people aspire to own at least a 1-carat diamond. DeBeers states, fewer than 1% of all women will ever own a 2 carat or larger diamond.,Most fancy-shaped diamonds are elongated in shape and appear larger than a comparable round brilliant diamond. In addition, fancy-shaped diamonds are priced less than round brilliants.,克拉重量,钻石价格=重量,2,基础价,K,克拉溢价,重量与直径、深度的关系,圆钻型的估重公式：,估算重量=直径 2 高 ,k,式中系数,k,取0.0061 0.0065 ,腰棱越厚，取值越大。,椭圆型的估重公式：,估算重量 = (长 +宽 ) 2 2 高 0.0062,Deers 4C,资 讯 新 概 念,更 注 重4,C,的 综 合 考 量。,每 颗 钻 石 都 美 丽 而 气 质 独 特。,每 颗 钻 石 的 特 点 都 决 定 了 它 们 独 一 无 二 的 价 值。,一 颗 钻 石 的 价 值 更 取 决 于 购 买 者 的 品 味 和 个 人 喜 好， 过 度 追 求 高 级 别 只 会 与 心 爱 的 钻 石 失 之 交 臂。,Contents,概述,Introduction,世界名钻,Famous Diamonds,钻石特性,Nature of Diamonds,钻石分级评估,Diamond Grading,钻石的鉴定,Testing,钻石产地,Localities,Diamond Testing,钻石的鉴定,钻石与其模仿品的物理性质,1、钻石的鉴别特征及方法,（1）外观特征,钻石具有典型的光泽、亮度和火彩特征，即强金刚光泽、高亮度、火彩强而柔和。,根据上述特征，有经验的人往往用肉眼观察就能初步区分钻石与其它仿制品。,(2)透视效应,有助于判断透明刻面型宝石的相对折射率。,钻石因折射率很高，只有极少量光能从亭部透过，故从亭部看似乎不透明，而折射率较低的仿制品因漏光较多显得较为透明。,将宝石放在有字迹的纸上，钻石没有透视现象，而大多数仿制品有程度不同的透视现象。,透视现象 钻石：无,立方氧化锆：轻微,钆镓榴石：中等,钇铝榴石：明显,其它(,N1.80)：,强,（3）面棱及腰围,钻石硬度最大，因而不易磨损，面棱一般较尖锐。,未抛光的钻石腰围面常呈独特的微粒状或蜡状外观，而仿钻腰围面常显得较平滑或有一系列平行琢磨痕。,钻石腰棱处有时可见到略微向内侧延伸的须状劈裂 纹（胡须）、残留的原始晶面及小三角形凹陷（蚀象）。,（4）放大观察,在显微镜下，当以适当角度照明，有时可见到钻石内部或延伸到表面的一些细微而直的透明纹理（生长纹），可区别于人造仿制品。,钻石常含有固态矿物包体，天然仿制品常含气液包体，人造仿制品一般较纯净，偶含气泡、未熔粉末、铂（铱）晶片等包体。,钻石是单折射宝石，无面棱重影现象。而有些仿制品（如合成金红石、锆石等）具有的明显双折射重影，以此可区别于钻石。,（5）硬度测试,钻石是最硬的物质，测试硬度无疑是一种最有效的鉴定方法，但有破坏性。在别无它法的情况下，可以谨慎使用。,将宝石的腰棱在刚玉硬度板上小心刻划，若能划动，可确定为钻石,。,（6）热导仪测试,钻石的导性极佳，而仿钻的导热能力都较差。,在室温下，钻石和仿钻的热导率为：,钻石：型 1000,W/(m),a 2600W/(m),刚玉：40,W/(m)，,仅次于钻石。,热导仪是基于钻石与仿钻的热导率有巨大差异而设计的，可以快速进行真伪鉴别。,2、钻石与其常见模仿品的区别,锆石,热导仪负反应,双折射大（沿一定方向具有双影）,硬度较小、脆性大，在珠宝首饰产品中长见有棱边不够尖锐、有纸蚀效应等现象,立方氧化锆（,CZ）,曾被称为“苏联钻”，也有误称为“方晶锆石”等，是目前为止最象钻石的一种人工宝石。,热导仪负反应,相对密度较大，硬度较小，据此可通过简单比较大小和简易测试来识别。,合成碳硅石（莫桑石, 美神莱,）,合成碳硅石是近年来用来模仿钻石的一种新产品，这种宝石的热导性也高，用一般热导仪也呈正反应而无法与钻石区别。,但合成碳硅石是六方晶系的宝石，具有双折射，沿一定方向在镜下观察可见双影，据此可区别于钻石。,合 成 碳 硅 石,Synthetic Moissanite,合 成 碳 硅 石(,Moissanite),背 景,基 本 特 征,能 否 有 效 地 检 测,主 要 鉴 定 特 征,合 成 碳 硅 石,Moissanite,新 的 钻 石 仿 制 品,合 成 碳 硅 石,由 美 国,C3,公 司 生 产,开 始 在 美 国 及 亚 太 区 销 售,是,CZ,的 改 进,硬 度 高 于,CZ，,比 重 接 近 钻 石,但 比,CZ,更 昂 贵,合 成 碳 硅 石,背 景,名 称 来 源,Henri Moissan,博 士,化 学 成 份碳 化 硅 晶 体(,SiC),天 然 产 出 极 少,颜 色 以 黑 色、 暗 绿 色 居 多,主 要 用 途 磨 料、 半 导 体 材 料,但 是，,C3,公 司 合 成 出 近 无 色 的 碳 硅 石,合 成 碳 硅 石,外 观 特 征,目 前 所 合 成 的 碳 硅 石 颜 色 从 近 无 色 到 浅 黄、 绿 及 灰 色；,大 多 带 有 较 为 明 显 的 灰 色 或 绿 色 色 调， 所 以 难 以 按 照 正 常 的,DZ,颜 色 分 级；,大 多 数 样 品 不 含 可 见 的 内 含 物；,不 具 透 视 效 果；,碳 硅 石 不 及 钻 石“ 亮”， 但“ 火 彩” 比 钻 石 强。,合 成 碳 硅 石,宝 石 学 性 质,双 折 率 为 0.043(,),mm,圆 形 切 割 重 量 为0.91 克 拉）,热 导 仪 下 的 反 应 与 钻 石 相 同， 普 通 热 导 仪 不 能 区 分 钻 石 与 碳 硅 石,合 成 碳 硅 石,宝 石 显 微 镜 及 放 大 镜 检 查,从 台 面 观 察， 亭 部 刻 面 的 棱 线 具 重 影；,抛 光 效 果 不 及 钻 石 的 抛 光 效 果； 棱 线 较 为 圆 钝；,抛 光 纹 常 为 同 一 方 向；,常 见 的 内 含 物 为 彼 此 平 行、 且 平 行,C,轴 的 白 色 针 状 物。,合 成 碳 硅 石,与 钻 石、 立 方 氧 化 锆(,CZ),的 对 比,碳 硅 石 比,CZ,硬,碳 硅 石 比 重 比,CZ,更 接 近 钻 石,碳 硅 石 的 导 热 性 与 钻 石 相 近,但 是， 碳 硅 石 具 双 折 射,碳 硅 石 的 性 质,合 成 碳 硅 石,检 测,普 通 热 导 仪 难 以 区 分,宝 石 显 微 镜 可 鉴 别,颜 色 及 抛,光 特 征,比 重 液 法( 甲 基 碘， 比 重 为3.30),C3,公 司 最 近 研 制 出 了590 型 检 测 仪， 售 价590 美 元； 市 场 上 可 买 到 其 它 类 型 的 检 测 仪。,3、,钻石的常见处理及其识别,人工改色,利用辐照和加热处理可以对钻石进行人工改色。按照不同的钻石类型以及辐照和热处理的情况，可产生各种颜色。最常见的颜色是绿色、褐色和黄色，其次是蓝绿和蓝色以及粉红红色。,识别方法：在天然褐色或粉红色钻石中可显示平直的色带。而在人工改色钻石中，颜色的分带往往平行于宝石的刻面；有的从台面看，其颜色图案象一把张开的雨伞环绕低面或在腰的四周见一暗色环。,激光处理（,Fracture Filled）,用激光处理可以去除钻石中的暗色包裹体，而使钻石看起来净度提高了。,识别方法：镜下可见圆形小孔延伸至宝石表面。,裂隙充填（,Laser Drilled）,利用玻璃或一些高折射率的无色透明物质填充钻石中的裂隙或激光孔，也可使钻石看起来净度提高了。,识别方法：在充填位置可见光晕效应。,此外，钻石还可能经过渡膜、涂层等处理，应予注意。,PVD,退 色 处 理 钻 石,(,NEW),技 术 背 景 资 料,就 目 前 所 知：,它 不 同 于 任 何 传 统 处