The internal refractive index of the cut standard diamond is very high, and almost no light can pass through the diamond pavilion to reach the table, so the bottom of the diamond is vertically placed on a piece of white paper with the black line of a pencil drawn on it. If you look vertically through the table, you can't see the black line, while the imitation diamond with low refractive index, such as zircon, can see the curved black line.
2. Harbin gas identification
Diamonds have high thermal conductivity, so we breathe a sigh of relief at them. If the water vapor on the surface of a diamond dissipates quickly, it is a real diamond. And if the water vapor on the surface dissipates slowly, diamonds may be imitations. However, this method is affected by the size and temperature of the diamond, so its use is more limited.
3. Water droplet identification
Clean and wipe the diamond to ensure that its surface is free of grease. Then, drop water on the diamond. If water drops can stay on a diamond for a long time, it is a real diamond. If the water drops disperse immediately, it may be a diamond imitation.
Tell if it's a diamond. How can it be a diamond by the sea? Even ordinary stones have transparent beauty.
How to tell whether it is jadeite jade generally has green, orange and white. If you know how to distinguish the authenticity of jadeite, you won't suffer from buying jadeite, and it's also very interesting to find out the original jadeite stone at home to check the authenticity. Here, I will teach you a few simple and quick ways to distinguish real jade from fake jade.
The easiest way to identify jade (listen to the old man, for reference only):
1, put jade glossy surface on your face or lips to feel cool.
2. Looking at the sunshine, there are some cloud-like things in jade, like cotton wool.
3. Jade is very hard, like a diamond, so you can draw a series of marks on the glass.
4, jade is cold, put a head on the jade, burn it with a lighter, and burn it with the jade head all the time.
How to tell whether the wedding ring bought by a new couple is a real diamond? How can couples get married without a wedding ring? This is not only an ornament, but also a witness to the beginning of happiness for two new people. So the choice of wedding ring is very important. However, newcomers do not have the ability to distinguish between true and false diamonds, and it is easy to buy bad diamond rings. In order to avoid this situation, it is very effective to sell money to make up for the identification method. The following is a brief introduction to a method of identifying the authenticity of diamonds without tools: 1, stroke identification: because of the oleophilicity of diamonds, you can draw on the diamond table with an oil pen. Don't worry, real diamonds won't leave scratches. If the lines drawn are coherent, it means that they are real diamonds. If the lines are not obvious or discontinuous, there is probably something wrong. 2. Breathing identification: natural diamond has good heat transfer ability and fast heat dissipation. Put the diamond to be tested close to your mouth and let the diamond to be tested be covered with a layer of light fog. At this time, immediately pay attention to the evaporation of the diamond fog. If it is a natural diamond, the fog will disperse immediately, otherwise the fog will stay on the fake diamond for a while before dispersing. 3. Water drop identification: Wipe the upper facet of the diamond clean and dip a drop of water on it with the end of a toothpick. The water droplets on a real diamond will be in the shape of small round water droplets. The water droplets on the fake diamonds will soon disperse. 4. Pencil identification: After the diamond is wetted with water, it will be carved with a pencil, and no pencil marks will be left on the surface of the real diamond. Transparent fake diamonds such as crystal, glass and tourmaline will leave traces. 5. Characterization and identification: The hardness of diamond is so strong that it is difficult to leave a notch on it with a blade. In addition, a slight scratch on the glass with diamonds will leave more obvious white marks. Fake diamonds do not have this phenomenon. 6, optical identification: real diamonds have a single refraction, with the characteristics of radiant, dazzling and bright, wearing a hand can not see fingerprints. Fake diamonds, such as crystals, have poor dispersion and low refractive index, and fingerprints can be seen through the crystals. Clean the diamond and put it on a piece of lined paper with the table facing down. If the diamond is cut in a standard way, the lines on the paper are invisible through the diamond, while most imitations allow enough light to pass through, at least some lines can be seen. 7, touch identification: because diamonds have affinity for oil, and people's finger skin will secrete some trace oil, gently touching the crystal face of diamonds with your fingers will have a sticky feeling. Use a magnifying glass, but this method requires some experience. Try it several times with your hands and slowly cultivate your feelings. For the finished diamond that has been inlaid, you can touch it by hand and check it with a magnifying glass, and you will find that the diamond is stained with more oil than the diamond substitute or other gems. 8, contact identification: diamond is crystalline carbon, with excellent thermal conductivity, with the tongue, cheeks, hands touch the diamond, the human body is constant temperature, if the diamond also heats up, it is an imitation. Real diamonds cool if they are left for a long time.
How to identify diamond 4C
Special case of diamond value
In general, the value of diamonds can be identified by 4C parameters, except colored diamond.
Carat weight
The weight of diamonds is measured in carats (also called cards). 1 carat = 200mg = 0.2g A carat is divided into one hundred parts, and each part is called one point. 0.75 carat is also called 75 cents, and 0.02 carat is 2 cents. Under other similar conditions, with the increase of diamond weight, its value increases geometrically; Diamonds with the same weight will have different values due to different colors, cleanliness and cutting. You can find high quality diamonds in every different size and shape. The most important thing is to find a diamond with the right size and style that you like. You might as well try it on at the jewelry store. When it looks and feels right, it should be yours.
Clarity (clarity)
Diamonds are crystallized from mantle magma deep in the earth, with complex environment, diverse components and extremely high temperature and pressure. After hundreds of millions of years of geological changes, it is inevitable that there are all kinds of sundries or defects in it. The color, quantity, size and location distribution of these inclusions have different degrees of influence on the clarity of diamonds. The clarity of a diamond is usually classified by using a magnifying glass with a magnification of 10 to classify the internal and surface defects of the diamond and their influence on the luster. According to China's national inspection standards, it is divided into LC, VVS 1, VVS2, VS 1, VS2, SI 1, SI2, P 1 and P2. Diamonds are divided into five grades: excellent, very good, good and relatively good. P-class drill is also called I-class drill. Diamonds below grade P are generally not used as gems, so they are generally only classified as grade P, and are no longer classified as P 1\P2\P3.
Color (color)
Diamonds have many natural colors, from precious colorless (white after cutting), rare light blue and pink to common light yellow. The more transparent and colorless, the more white can penetrate, and the richer the color after refraction and dispersion. The grading of diamond color is determined by technicians repeatedly comparing the diamond to be graded with the standard color colorimetric stone in the grading environment of professional laboratories. The whitest diamond is set to D (that is, starting from the first letter of the diamond). The color of diamonds is divided into 1 1 grades, which are D, E, F, G, H, I, J, K, L, M and N in turn.
Cut (cut)
Diamond cutting refers to the accuracy of its cutting and grinding ratio and the perfection after finishing. Good cutting should reflect the brightness and fire color of the diamond as much as possible, and try to keep the weight of the original stone. The cutting grades of IGI International Gemological Institute are divided into ID (standard), EX (excellent) and VG (very good) G (good) from high to low, and the domestic national inspection is divided into EX (excellent), VG (very good) and G (good). In China, ordinary people generally measure the value of diamonds by weight. Actually, it is not scientific. Because small diamonds are very popular in China. Therefore, the more popular concept is high-quality diamonds. High-quality and bright diamonds generally grasp the three principles of 4C: clarity, color and cut, and the three standards must reach a certain standard at the same time.
It is difficult to tell you clearly how to identify diamonds in one sentence. The identification of a diamond depends on its refractive index (2.4 17), dispersion (0.044) and hardness (10, which is the hardest natural substance). If it is a finished product, you can also look at its faceted edge and fire color. Generally, a diamond barrel has a corresponding certificate, so the reliability can be good.
How to identify vvs diamonds can't be identified by individuals, and it needs the special equipment of authoritative organizations to identify them.
How to identify condyloma acuminatum? The lesions of patients with condyloma acuminatum are small red papules at the beginning, and then grow up gradually. The lesions are uneven and soft, some of them are cauliflower-shaped, with pedicels, and the surface is moist. When they are soaked in secretions, they can be gray, dirty gray or red. Initial symptoms of condyloma acuminatum: a long time, erosive exudate on the surface, sometimes scratching with itching, secondary bacterial infection, purulent secretion on the surface, peculiar smell and pain.