First, Burmese jade is also called jadeite. It was very popular in the late Qing Dynasty and the early Republic of China: for example, a jade age tube by Rong Lu, Minister of the Interior of the Qing Dynasty, was worth 13000 taels of gold. In the mid-1930s, Wang Tie Yuting in Beijing had a bracelet, which was sold to Du in Shanghai for 40,000 silver dollars. Myanmar jadeite is bright and clean because of its high hardness. Moreover, good jadeite is bright and peaceful in color and has high preservation and collection value, so it is called "the king of jade". It is loved by many people who love and wear jade. Japan and New Zealand also regard jade as their "national stone". Due to the special geographical relationship that jadeite is produced in Myanmar, which is close to China, and most of the finished products are processed in China, and the special preference of China people for jadeite, western countries generally consider jadeite as China's "national jade".
Second, the color of Burmese jadeite. Due to different regional customs, the color of Burmese jadeite is slightly different. In the jade kingdom of Myanmar, jadeite can be divided into three categories, with a grade of 12. The domestic jewelry industry divides jadeite into more than 30 grades according to its color. Generally speaking, the tones of Burmese jade can be roughly divided into the following six types. ?
1, white. Basically does not contain other impurity elements.
2, red. Contains the chemical element iron < FC3+ >
3. green. < Cr > containing more than 2% chromium?
4, black. Containing more than 2% < 〈Cr〉 > and Fe < Fe2+ >
5, purple. Containing the elements chromium, iron and cobalt
In particular, the green color in Burmese jade can be worn regardless of status, status, age and gender, except for its bright color and excellent durability. Therefore, it conforms to the implicit, peaceful, Wen Ya and cordial character of China people. The social demand is growing day by day. Prices have also doubled or even hundredfold. At present, the price of a jade bracelet in the international market has reached 10 million yuan. Even Myanmar jadeite ornaments with slightly inferior jadeite color are expensive as long as they are genuine A goods with sufficient water head, clear technology and harmonious colors.
Third, the quality and identification knowledge of Burmese jadeite. No matter from the mineral resources or mining capacity of Burmese jade, good jadeite is very limited, so some speculators and mercenary businessmen "take advantage of it". A large number of fake and fake goods, profit from it. Even in the emerald kingdom of Myanmar, fakes abound; Fake stones and ornaments can be seen everywhere.
At present, there are four kinds of Burmese jade popular in the market, according to the level of authenticity:
A goods are both natural texture and natural color. The identification method mainly focuses on the following three points:
(1) Look before you leap. Due to the relationship between mineral resources and mining volume and the specific conditions of large demand, there are few good Burmese jadeites on the market at present. In particular, there are few varieties with green color and bright ground color.
(2) Generally, varieties such as Mabel Miao, spinach green, scarlet or violet floating flowers are common.
(3) Observed by naked eyes under the light, the texture is delicate, the color is soft and the stone lines are obvious; Slight impact, crisp and pleasant voice; Holding it in your hand has a heavy feeling, which is obviously different from other parts of the stone.
Goods B will have jadeite with black spots, commonly known as "dirty". Use strong acid to soak and corrode to remove dirt and cotton to increase transparency, and then use high pressure to inject epoxy resin into the microcracks caused by strong acid corrosion to fill the cracks.
(1) The color of B goods was good at first. If you look closely, the color will become evil. If you look at it under a lamp, the color transparency will be weakened.
(2) Within two years, B goods gradually lost their luster, were full of cracks and became ugly. This is caused by the strong acid destroying its original quality.
(3) The density is reduced and the weight is reduced. Slight impact, low voice, lost the crisp sound of a cargo.
C the goods are completely artificially colored.
(1) At first glance, the color is not right and evil.
(2) Looking closely under the lamp, the color does not naturally exist in jadeite crystals, but is filled in the cracks of minerals, showing a network distribution of colorless roots.
(3) Observing with Charles filter, the green color becomes red or colorless.
(4) The surface color can be removed by scrubbing with powerful decoloring agent or turned brown.
D goods, D goods pretending to be jade ornaments mainly have the following two categories.
(1) jade. That is, other jadeites pretend to be jadeites. There are mainly Thai jadeite and Malaysian jadeite, Nanyang dushan jade, Qinghai jadeite, Miyu, Australian jadeite and Dongling stone. The differences between the jadeite mentioned above and Burmese jadeite are as follows: First, the hardness is low; Second, low density (light weight) and weak luster. ?
(2) Green glass and green plastic. Most of these substitutes are dull and ugly, and their luster is very weak. The relative density is very light, the hardness is low (it can be carved with nails), and there is no cold feeling.
Discrimination between true and false crystals
(1) At first glance, rock crystals are often influenced by the environment and always contain some impurities. When you look at the sun, you can see faint or even tiny stripes or catkins. However, fake crystals are mostly made of inferior crystal slag and glass slag, which are melted, polished and colored, without uniform stripes and catkin-like substances.
(2) Lick your tongue: Even in the dog days of hot summer, licking the surface of the crystal stone with your tongue will feel cold and cool. Fake crystals are not cool.
(3) Illumination: When the crystal is placed vertically in the sun, it can emit beautiful light from any angle. Fake crystals can't.
(4) Hardness: The hardness of the crystal is very high, and it will leave no trace when lightly scratched with gravel on the jewelry; If there are streaks, it is a fake crystal.
(5) Inspection with a polarizer: the rock crystal rotates 360 degrees under the polarizer, with four bright and four dark changes, while the fake crystal does not change.
(6) Check with dichroism: natural amethyst has dichroism, while fake amethyst has no dichroism.
(7) Magnifier inspection: under the transmitted light, the bubbles that can be found can be basically classified as pseudocrystals.
(8) Check with hair: If the crystal is placed on a hair, the human eye can see the double shadow of the hair through the crystal, it is a rock crystal, mainly because the crystal has birefringence.
(9) Test with a thermal conductivity meter: set the thermal conductivity meter to 4 squares of green to test the gem, and the rock crystal can rise to 2 squares of yellow, while the false crystal does not rise, and when the area is large, it will rise to 1 square yellow.
Discrimination between natural and synthetic crystals