Identify diamonds:
Oiliness test: use a special pen or ballpoint pen dipped in oily ink to draw a line on the diamond table, which will leave an uninterrupted straight line. However, other imitations are not lipophilic, leaving intermittent dotted lines at the scribe line.
Water drop test: the water drops on the diamond will remain spherical for a long time, while the water drops on the imitation will disperse in a short time.
Breathing test: breathe into the diamond, if the water vapor on the diamond disappears, it will become a real diamond immediately; If the water vapor stays on the diamond for a few seconds and then disappears, it is a fake diamond.
Sensory test: At room temperature, diamonds and their imitations are much cooler when you touch them with your tongue.
A simple way to identify diamonds
With the increasing demand for jewelry and diamonds, the market for fake diamonds such as artificial diamonds is expanding, and even some jewelry operators can't tell the difference. Here are some simple ways to identify the authenticity of diamonds.
1, single refraction of diamond
The single refraction of diamond is determined by its essential characteristics. While other natural gemstones or artificial gem are mostly birefringent. When the fake diamond is observed with a magnifying glass of 10 times, it is easy to see that the edges and corners overlap, and two bottom lights are exposed at the same time from the slightly inclined front. If the difference in birefringence is small, such as zircon, you can also see the image of overlapping background light.
2. Adsorption of diamonds
Diamonds have a certain affinity for grease and dirt, that is, oil stains are easily adsorbed by diamonds. So touching the diamond with your fingers will feel sticky, and your fingers seem to feel sticky. This is not found in any gem. This method needs training to master the nuances.
3. Characteristics of straight lines
The surface of the diamond is polished very smoothly. Dip the pen in ink and cross the diamond. If it is a real diamond, the surface will leave a smooth and continuous line, which is characterized by a straight line. Forgery will leave dots and lines. Observation in this way should be made with the help of a magnifying glass.
4. Unique diamond luster
Under the incandescent light of 100 degree, it is easy to see which diamond has diamond luster by comparing with the counterfeit. This method should not be carried out in too dark or too strong light.
How to tell the authenticity of diamonds?
How to distinguish real diamonds from "Soviet diamonds"
Real diamonds are expensive, and fake diamonds are often passed off as real diamonds. Cubic zirconia is a synthetic compound used in the mid-1970s. Its refractive index, dispersion and other optical properties are similar to real diamonds, and they are all isotropic. When polished into a diamond shape, cubic zirconia is no different from real diamonds in appearance. If you don't use special methods to identify, even some gem practitioners are difficult to identify. Because the former Soviet Union first introduced cubic zirconia diamonds, it is often named after "Soviet diamonds" in business. In fact, the former Soviet Union also produced real diamonds, and its output occupies an important position in the world. The following table is a comparison of the main characteristics of real diamonds and cubic zirconia. ?
As can be seen from the above data, the difference between real diamonds and "Soviet diamonds" can be distinguished by testing hardness and specific gravity. However, it is inconvenient to measure the specific gravity with toxic heavy liquid, because the hardness is easily destroyed. In addition, gem particles are small, so it is not easy to distinguish authenticity by hand feeling. At present, there is an advanced, rapid and accurate method to identify the authenticity of diamonds by thermal conductivity. The specific thermal conductivity of real diamonds is between 16000- 18000, while that of "Soviet diamonds" is only between 50- 100. So in the early 1980s, a kind of "thermal conductivity meter" was designed. After many improvements, a portable pocket thermal conductivity meter has been produced. After the probe of the thermal conductivity meter is heated, the thermal needle contacts the diamond to be measured. If it is a real diamond, the heat on the thermal needle will soon be transmitted from the real diamond, and the LED of the thermal conductivity meter will display it and chirp at the same time. If the hot needle touches the "Soviet diamond" or other gems with poor thermal conductivity, the LED will not flash upward and will not chirp, but it will also chirp; If the hot needle touches the "Soviet diamond" or other gems with poor thermal conductivity, the LED will not flash upward and will not chirp, so it is the most convenient means to identify the authenticity of diamonds with a thermal conductivity meter.
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Prove that there must be.
Now it's the overlord clause, so we can only sell it and not refund it.
How to quickly distinguish the authenticity of diamonds with naked eyes
Hello, this is a bit difficult, but there is still a way. First, the gemmology of the most common imitation diamonds, such as zircon, mosanite and white crystal, is unclear for several years. Say it briefly.
1. If there is a diamond, draw a straight line on white paper, turn the diamond upside down, and look down from the bottom of the diamond, you can vaguely see that the whole piece is black, mostly diamonds, while zircon can vaguely see two curves. The reason is that the fire color of zircon is stronger than the characteristic (refractive index) of diamond.
2, there is a simpler way, stick a little water with a small needle and drop it on the surface of the diamond. If the water drops suddenly disperse, it may be a diamond, because diamonds have the characteristics of lipophilic and hydrophobic.
3. There is another one. If you have an artificial ruby and sapphire (natural and a little wasteful), you can mark it with a diamond, which should also be a real diamond. Note that fakes can also be marked, but they can be erased by hand. This is done by the gemstone hardness method. Diamond has the highest hardness, then corundum (red sapphire) is removed, and then it is expected.
If your eyesight is good enough, you can look at a facet of the diamond, change your perspective and look at the fire color. Zircon is particularly bright, and you can see red light and blue light appear at the same time. If you really drill, you should see not only the red light, but also the blue light. The same characteristics as the first point.
If 1234 all see the same result, then the probability of real drilling is very high.
I hope I can help you. If yes, please choose my best answer, and I will continue to answer for you.
How to identify the authenticity of diamonds?
1, single refraction of diamond
The single refraction of diamond is determined by its essential characteristics. While other natural gemstones or artificial gem are mostly birefringent. When the fake diamond is observed with a magnifying glass of 10 times, it is easy to see that the edges and corners overlap, and two bottom lights are exposed at the same time from the slightly inclined front. If the difference in birefringence is small, such as zircon, you can also see the image of overlapping background light.
2. Adsorption of diamonds
Diamonds have a certain affinity for grease and dirt, that is, oil stains are easily adsorbed by diamonds. So touching the diamond with your fingers will feel sticky, and your fingers seem to feel sticky. This is not found in any gem. This method needs training to master the nuances.
3. Characteristics of straight lines
The surface of the diamond is polished very smoothly. Dip the pen in ink and cross the diamond. If it is a real diamond, the surface will leave a smooth and continuous line, which is characterized by a straight line. Forgery will leave dots and lines. Observation in this way should be made with the help of a magnifying glass.
4. Unique diamond luster
Under the incandescent light of 100 degree, it is easy to see which diamond has diamond luster by comparing with the counterfeit. This method should not be carried out in too dark or too strong light.
High hardness synthetic diamond
The R&D Center of General Electric Company of the United States has synthesized synthetic diamonds with atomic density per unit volume higher than that of any existing solid substance, and the hardness is higher than that of natural diamonds, which is the hardest material in the world. It contains 99% carbon 13 isotope and natural diamonds. According to scientists' observation, with the increase of carbon isotope density 13, the distance between atoms will be slightly reduced, which makes the hardness of artificial diamonds exceed that of natural diamonds with slightly loose atomic arrangement. In the process of synthesizing synthetic diamonds, scientists first precipitate carbon in methane gas rich in carbon isotope 13 into small diamond fragments by chemical evaporation, then decompose these small fragments with very high pressure, and then recrystallize the massive diamond with the maximum weight of 3 carats.
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Diamond is one of the hardest gems found on the earth, which symbolizes eternal love and is cherished by people. Many people want to have a beautiful diamond for their loved ones, but how to buy a diamond that they like and are worth the money is a science.
What is a diamond? Diamond is the only gem in the world that is made of a single carbon element. It is the hardest natural substance at low temperature and high pressure.
What is the 4C of a diamond?
The clarity and flawless degree of a diamond.
Colored diamonds come in different colors. Generally speaking, the whiter the better.
Cutting involves the shape and proportion of diamonds, as well as the factors that affect the aesthetic feeling of sparkling fire colors.
Actual weight of carat diamond (1ct = 0.2g = 100 min)
The actual weight of how much diamonds you have to pay depends on these four C's, and these four C's are the biggest factors that determine the price of the fifth C.
How to identify diamonds?
1, if you draw a line with a pen and ink on the table of a diamond, it will be an uninterrupted straight line, while other gems are intermittent dotted lines, because diamonds are lipophilic.
2. If the diamond is yellow when viewed from the side, then the Yan * * * level is generally below the "I" color, because when viewed from the front of the diamond, only the shiny fire color can be seen, unless the diamond is yellow, the color cannot be seen clearly.
3. When we distinguish diamonds from other imitation gems, we can use a breath of "ha" to form steam on the surface of diamonds. Diamonds conduct heat quickly, and the steam will disappear in one second, while other gems take a long time. Generally, diamond pens for jewelry are made according to the principle of heat conduction.
Finally, when you decide on diamonds, it is very important to ask the merchant for the certificate of a formal testing institution, which will give you better protection. ...
How to identify the authenticity of diamonds?
There are many ways to identify the authenticity of diamonds. The simplest way is to go to a professional identification agency. There are other methods as follows:
(1) Look at the color: Because diamonds reflect light strongly, you can put your mouth against the diamonds to make them not reflect light, so that you can see the color more accurately. The order of color from good to bad is: colorless transparent (or crystal color) white, light yellow and yellow.
(2) Look at the purity of crystal transparency: This mainly depends on how many impurities are contained in the diamond. High-grade diamonds are still flawless when placed under a magnifying glass for more than ten times. Generally, those with few impurities are called "microfilaments", while those with many impurities are called "half flowers", "one flower" and "two flowers", and so on.
(3) Looking at the lathe operator: From the perspective of refraction, the diamond lathe operator's angle is accurate, and every angle and surface are the same. The higher the accuracy of this angle, the higher the grade of the diamond. Real diamonds have 57 or 58 reflecting surfaces (with a few exceptions).
(4) There is a simple way to identify genuine and fake diamonds, that is, if a diamond is put in your hand, you can't see the fingerprints, while fake diamonds such as rhinestones, white rubins (also known as synthetic diamonds) and Ceylon diamonds can see the fingerprints. Claudie's diamond ring is trustworthy.
How to tell whether a diamond is genuine or not?
How to evaluate the quality of diamonds
The evaluation of diamonds should be based on the four standards of "clarity, color, cut and weight".
1. Clarity: Diamonds are natural products with some flaws. These defects are small crystals, clouds, pinholes and small cracks wrapped in the diamond during its growth. Clarity grading is carried out by professionals under the magnifying glass of 10 times. According to the size, quantity and location of the observed defects, it is divided into five grades, namely 10.
2. Color grading: Color grading is obtained by observing the obvious degree of yellow (brown) tone in yellow series diamonds, and the classification of diamond color grading is completed by professionals in a specific environment. The color of diamonds is divided into 12 grades, and different color grades are represented by English letters.
3. Cutting classification: Through the measurement and observation under the microscope, the quality of diamond cutting and grinding process is classified, and the ratio instrument is often used for classification. The degree of modification is the symmetry of diamond cutting and grinding and the evaluation of surface polishing quality. As a consumer, we should judge the quality of cutting from the following aspects: whether the diamond is bright, whether the fire color is obvious, whether the shape is symmetrical, whether the surface is damaged and so on.
4. Quality (commonly known as weight): it is an important factor to evaluate the value of diamonds. The mass unit of diamond is gram (g), which can also be expressed by (ct), lg=5ct. In fact, most of the weighing is directly weighed by carat scale, and the carat value is reserved to two decimal places, and the third place is completed in eight rounds.
According to the clarity and color grade of inlaid diamonds, the quality of inlaid diamonds is divided into five grades: excellent, very good, good, good and general. The influence of diamond cutting on quality is not considered.
How to buy diamonds
When buying diamonds, it is best to choose products from reputable diamond jewelry stores or famous manufacturers and shopping malls. Don't rush to buy, ask carefully to see if it is consistent with your knowledge in this field. Ask for invoices and quality guarantee. For the sake of prudence, you can go to a trusted jewelry appraisal station to get a "diamond appraisal certificate". This is the "physical examination form" and "ID card" of the diamond. If the product is accompanied by an appraisal certificate, the following criteria can be used to compare one by one-whether it conforms to the real thing, who appraised it, when is the date, whether it is filled in correctly and clearly, and whether there are any omissions. The price of diamonds is mainly determined by four indicators: clarity, color, cut and quality. In the total price of diamonds, weight accounts for 40% ~ 60%, clarity accounts for 15% ~ 25%, color accounts for 15% ~ 20%, and cutting accounts for 20% ~ 35%.
Say the weight first. The weight is priced by grades, such as 18' ~ 22' is 20', 23' ~ 27' is 25', and 28' ~ 39' is 30', and the price difference per carat is 3500 ~ 10000 yuan. Therefore, although the price difference between 22' and 23' and 27' and 28' is only 0.0 1 carat, there is a grade difference in price, and the price difference is 350 ~ 1000 yuan. If you choose the weight reasonably, you will save money
There are five grades of clarity, and the colors are 1 1 grade. Their relationship is as follows: the clarity difference is 10% ~ 15%, that is, the clarity difference of VVS, VS and ST is 3000 ~ 5000 yuan per carat, which is 3000 yuan different from that of 1 piece with the same weight.
Colors are divided into three categories, 1 1 grade, price difference between types 10% ~ 15%, and difference between grades 10%. For example, a VS white diamond of about 3000 yuan, the color accounts for 450 yuan in the price. For the same VS white diamond, the difference between J and H can be 20%, which is the difference 90 yuan. Cutting accounts for 20% ~ 35% of the total price. Based on 30% calculation, the benchmark cutting price of a 3,000-yuan diamond is 900 yuan. Because the quality of cutting affects the degree of "fire" and the size of the ring surface, different cutting workers have certain price differences, with the lowest cutting in Hong Kong and the highest cutting in Belgium. Generally, Belgian cuttings are 25% ~ 30% higher than Israeli cuttings, and Israeli cuttings are 65,438+05% higher than Indian cuttings. For example, an Indian cut diamond worth 3,000 yuan (900 yuan cut), Israeli cut 1035 yuan, Belgian cut 1290 ~ 1350 yuan. Therefore, a 3000 yuan Indian cut VS white (J-grade) diamond is replaced by an Israeli or Belgian cut VS white (H-grade) diamond, and its price is about 3225 ~ 3540 yuan.
The proportion of brands in the price is still uncertain. Because the jewelry industry in China has already started. ......
How to tell whether a ring is genuine or not? Where are the diamonds? thank you
Intuitive recognition
Perspective test-clean the gem with a round diamond cutter, put it on a piece of white paper with lines, and judge whether the gem is a diamond by observing the lines on the paper. If it is a standard round cut diamond, the lines on the paper cannot be seen through the diamond (synthetic strontium titanate and synthetic rutile are similar to diamonds and have no perspective effect). However, due to the different refractive index, most imitations have enough light leaking from the pavilion surface, and some lines on the paper can be seen through perspective observation.
Brightness estimation-the ability of external reflection and total internal reflection of gem crown to refract light, which is called brightness. When diamonds and their imitations are placed in the same light source and environment, the standard round diamonds with fine cutting are observed from the bottom, and almost all the light entering from the crown is reflected by the crown, showing strong brightness. However, the refractive index and cut of imitation are different from that of diamond, and the light entering from the crown will leak out from the pavilion to varying degrees, thus reducing the brightness.
Oiliness test-Draw a line on the diamond table with a special pen or ballpoint pen dipped in oily ink, which will leave an uninterrupted straight line. However, other imitations are not lipophilic, leaving intermittent dotted lines at the scribe line.
In the water drop test, clean the mesa of diamond and imitation, drop a little water each, and observe the time and contour of the water drop. The water droplets on the diamond will remain spherical for a long time, while the water droplets on the imitation will disperse in a relatively short time.
Breath test-put the sample to be tested and the known diamond sample together on the glass, blow on them and observe the disappearance of the fog. The fog on the diamond disappears quickly, but the fog on the imitation disappears slowly.
Sensory test-diamond and its imitation are touched with the tip of your tongue at room temperature. The diamond is much cooler than the imitation.
I wonder if I can help the landlord. The best way is to go to the appraisal center for appraisal, which is only a few tens of dollars. You don't need a certificate for identification, and it is even more expensive to ask for a certificate.
How to tell whether a diamond is genuine or not?
Simple diamond identification method
Oiliness test: use a special pen or ballpoint pen dipped in oily ink to draw a line on the diamond table, which will leave an uninterrupted straight line. However, other imitations are not lipophilic, leaving intermittent dotted lines at the scribe line.
Water drop test: the water drops on the diamond will remain spherical for a long time, while the water drops on the imitation will disperse in a short time.
Breathing test: breathe into the diamond, if the water vapor on the diamond disappears, it will become a real diamond immediately; If the water vapor stays on the diamond for a few seconds and then disappears, it is a fake diamond.
Sensory test: At room temperature, diamonds and their imitations are much cooler when you touch them with your tongue.
First of all, we can judge the authenticity of diamonds from two aspects: color and clarity. The color of synthetic silicon carbide is generally yellow, which can be clearly felt by the naked eye, even more yellow than the light yellow and white diamonds sold in the market. With the help of a magnifying glass, it can also be observed that there are thin tubular inclusions and obvious surface edge ghosting phenomenon. Secondly, when consumers buy diamond jewelry, they must ask the merchants for a diamond appraisal certificate or a diamond grading certificate to ensure the quality of the diamond jewelry they buy.
How to verify the authenticity of diamonds?
It is often used by those who are more experienced to identify the authenticity of diamonds through manual models. Touching the curved surface of a diamond with your fingers will feel sticky, which is unique to real diamonds. Because diamonds have affinity for oil, and there is a trace of hand oil secreted from human finger skin, this skin oil will feel sticky when it comes into contact with the crystal face of the stone because of the affinity of diamonds for oil. And those other materials naturally don't have this special feeling.
When identifying, you need to wet the diamond with water first, and then carve it gently with a pencil. On the crystal face of a real diamond, there is no trace where the pencil crosses, but if it is not a diamond, but a material such as glass and crystal, it will leave traces on the surface.
Generally speaking, pencils are used to identify diamonds. This method has high accuracy. But in the appraisal, we should pay attention to some inlaid old diamond jewelry, which is not suitable for water seepage, because if it is inlaid with copper or silver, it is easy to oxidize. In addition, generally speaking, the crystal face of a diamond also needs to avoid contact with oil, dust and objects.
How to identify the authenticity of diamonds? Method of distinguishing natural diamonds from synthetic diamonds
However, when people buy diamonds, they sometimes buy fake diamonds (that is, some fake materials or artificial diamonds) if they are in informal places or brand-free shops, resulting in heavy losses. At present, the common diamond-like materials in the market mainly include: natural colorless and transparent gemstones (such as crystal), artificial cubic zirconia (also known as Soviet diamond, CZ), strontium titanate, yttrium aluminum garnet (YAG), gadolinium gallium garnet (GGG), synthetic silicon carbide (moissanite), glass and so on. A method to identify the authenticity of diamonds by multiplying 10 by 1 with a magnifying glass. Look at the characteristics of the prism. Diamond has high hardness and sharp edges between facets, while substitute or imitation diamond has low hardness and the edges are easy to wear and smooth. 2. Fire-colored diamonds have strong luster and soft fire, while the fire of imitation diamonds CZ and strontium titanate is too strong and dazzling, and YAG flash appears sluggish. 3. Seeing that lipophilic diamonds have affinity for oil, they are easier to get oil than imitation diamonds and substitutes. 4. Look at the speed at which the fog dissipates, and breathe on diamonds, imitation diamonds and substitutes at the same time. The fog on the diamond dissipates faster. In addition to the above characteristics, an imitation can be distinguished from a diamond according to its personality characteristics. For example, zircon has a high density, so zircon is heavier than a diamond of the same size. For example, due to the high birefringence of zircon, the ghost phenomenon can be clearly seen at the edge of zircon after magnification; Glass imitation diamonds often contain bubbles, which is the key point to identify the authenticity of diamonds. Simple methods to identify the authenticity of diamonds For example, for ordinary people, the simple and feasible methods to identify the authenticity of diamonds are: 1. Pencil identification method After the diamond is wetted with water, it is scraped off with a pencil. The surface of the real diamond will not leave pencil marks, while the colorless and transparent fake diamonds such as crystal, glass and tourmaline will leave marks. 2. Pen identification method After dipping the pen in ink, draw a line on the diamond. When a real diamond is observed under a magnifying glass, its surface will leave smooth and continuous ink lines without broken marks. The lines left by fake diamonds are often made up of small dots. The hardness of diamond is very strong, and the tip of diamond is quite sharp. When a diamond is scratched lightly on the glass, it will leave obvious white marks, while a fake diamond does not. 4. Drip identification method Wipe the upper table of the diamond clean and dip a drop of water on it with the end of a toothpick. The water drops on the real diamond will show a moderate small circle, and the water drops on the fake diamond will quickly disperse. 5, optical identification method Real diamonds have the characteristics of single refraction, radiant and dazzling brightness, but you can't see fingerprints when you wear them on your hands. Fake diamonds, such as crystals, have poor dispersion and low refractive index, and fingerprints can be seen through the crystals.