Jadeite - Nephrite Jade Quality
Natural Jadeite Jade Bangle
Nephrite and Jadeite
Marble, Jade, is one of the oldest known gemstones, with a history spanning more than 7,000 years. But it was only in 1863 that gemologists discovered that Marble is actually two distinct and fairly obvious minerals: Nephrite and Jadeite.
- Nephrite Jade: Medium to dark green or grayish green, or white, yellowish, or reddish. Hardness 6.0 - 6.5
- Jadeite Jade: Green and also white or pink, red, black, brown and purple. The most valuable color 'Imperial green' Jade is only available in Jadeite. Jadeite has higher transparency and gloss. Hardness 6.5 - 7.0
Jadeite is rarer and more valuable than Nephrite. Burma Jadeite Jade mined in Burma is the most popular.
Marble is not transparent, but has a brilliant luster. The Cabochon cut is the best cut suitable for Marble, cut as fine as decorative paintings, bracelets, rings, tubes and beads or artistic engraving.
The rarest and most valuable Marble is called Imperial green Jade, colored by chromium. Although it has a slightly more yellowish tint, Imperial green Jade has the same color and transparency as the beautiful Emerald. Grade A Jadeite is natural untreated Burmese jadeite with 100% natural color.
Jadeite Jade mines are mainly in Burma (Myanmar). Also available in other countries: Russia, Canada, Japan and USA.
Nephrite Jade mines are located in: China, Korea, New Zealand, Australia, Canada, Russia and the United States.
Natural Nephrite Jade Guanyin Buddha Pendant in 14K White Gold
Legend of Marble
With beauty and wide-ranging expression, Marble has been especially attractive to mankind for thousands of years.
Marble has been known for more than 7000 years. Since ancient times, it has been respected for its toughness, making it the ideal material for weapons and tools. More than 3000 though, Jade is known in China as the 'royal jewel'. In the vast history of art and culture in China, jade has always had a very special meaning, being used not only for sacred gods and figures of worship, but also in tomb equipment. for members of the royal family.
All traditional Chinese jade is nephrite, because in China there are large reserves of nephrite, but no jadeite.
Jadeite first came to China from Burma in the 18th century. Before the arrival of jadeite, the Chinese tended to appreciate the translucent white nephrite. But jade from Burma comes in more colors, including green, lavender, yellow, black and white.
The pre-Columbian, Mayas, Aztecs and Olmecs of the Americas also respected and valued Marble more than gold. In ancient Egypt, Marble was enchanted as the stone of love, peace and balance, harmony.
In Asia, it is gathered as an antique. In the West, many people like to gather Marble in cigarette cases, tobacco pipes, small bowls or rings. In America and Europe, pure white or yellow with pale pink is highly respected, and green and apple green are especially valued.
Today, jade is seen as a symbol of energy, beauty and preciousness. It includes Confucian chastity, wisdom, justice, compassion, humility, and courage. Marble is considered 'Stimulating creativity, mental flexibility, balance and harmony'. Therefore, Marble brings us joy, vivacity and happiness. However, it also symbolizes female eroticism.
Quality Marble
To understand the value of jade, one must look beyond its durability and its role as a beautiful gemstone and jewelry.
Jade is a sacred gemstone with great significance in Chinese culture. So the value of jadeite has increased significantly along with China's economic growth. The Chinese have revered good blue Jadeite since its discovery in Myanmar.
Jadeite with its luminosity, sleek, transparent and beautiful color has the highest price of any gemstone on the international market today. Jadeite has a higher commercial value than Nephrite.
The three most important qualities of Jadeite are color, transparency, and texture.
1. Color
Color is perhaps the most important factor in marble valuation. Jadeite color is quite diverse: colorless, white, gray, green (green), yellow, orange, pink purple, red, black ... The color range from dark (strong) to light, or dark. Jadeite color is often unevenly distributed, forming small or large spots, stones often have 2 or more colors, so pure and evenly distributed types are very rare. The market often uses the color of the available objects to call the color of gemstones to help consumers easily visualize such as emerald green, apple green, bean green, oil color, mondo...
Marble has a wide color range. The highest value is the strong & fresh Green color called Royal Jade. - Courtesy Mason-Kay Fine Jade Jewelry
The current popular Jadeite color is green, the Vietnamese market calls it a ly color, the lighter the green, the lower the value. The most valuable is emerald green (like the color of emerald), which is a strong and bright green. Jadeite of this color and of high transparency, known as Royal Jade, is the most valuable and extremely rare jadeite. Other greens that are lighter, but easier to find, are apple green, pea green, which resembles apple pods and pea pods.
2. Transparency and stone architecture
This factor together with the color determines the beauty of marble. Normally, Marble is never as transparent as other single-mineral gems such as Diamond, Ruby. Because the stone is composed of micro-grains and micro-fibers, most of Marble is blocking light (not allowing light to pass through the stone), some are translucent and most are semi-transparent (semi-transparent), but this type is very rare.
Most marble is opaque, very little is semi-transparent. In the picture, the leftmost three are opaque, then the translucent one, the rightmost one is the clearest (semi-transparent). 
This pair of jadeite bracelets is extremely rare. Both have an inner diameter of 53.4 mm and a thickness of 9.6-9.7 mm. This pair of Marble rings is almost colorless and has emerald green spots. Especially the transparency is very high, so it is called glass jadeite. This pair of marble rings was sold for USD 116,600 at an auction held by Christie's in Hong Kong in November 1999. (Picture of Christie Hong Kong and Tino Hammid)
The size and uniformity of the microparticles affect the transparency. Many rocks have medium and coarse grains that make the stone more prone to turbidity, whereas extremely small and homogeneous particles make the stone clearer. In the market, marble with high clarity is called glass marble (Figure 5). In terms of value, the clearer the marble, the higher the value.
3. Impurities
Impurities in Marble are the content of substances that are not the minerals of Marble (jadeite or Nephrite). This feature cannot be identified with the naked eye, but we can feel it through the clarity and color of the stone. The purer the marble (higher content of jadeite or Nephrite in the stone), the clearer the stone will be, and the more even color will be. Some impurities are brown, gray and black which reduce the beauty of the stone and of course reduce their value. To determine whether a rock is marble or not, jadeite or nephrite, densitometry and absorption spectrometry methods can be used.
Marble is a multi-mineral stone, with many impurities, so most of it is uneven in color. The image above shows the level of color evenness increasing from right to left.
4. Fracture degree
Includes voids and small cracks. The boundaries of microparticles and fibers in marble form micropores. The fissures are created by natural compressive forces after the rock has formed. The manufacturing process or the impact when worn can also create small or large cracks. Small cracks caused by natural processes are often filled with material, which is a type of impurity that often has a different color than the original rock causing uneven color. Micropores have little effect on rock strength, but fractures can. Marble is very tough, difficult to chip, break, but if the stone has large cracks, when strongly impacted, the stone will be split and broken according to these cracks (bracelets are the most vulnerable). . However, when making, the glue or wax covered all the micro-cracks, the buyer cannot see them even with 10x magnification. With specialized equipment in the gemological laboratories, experts can determine the small cracks and how badly they affect marble products.
5. Weight, size
The larger the marble, the higher the value. If the Marble is of precious quality, the processing places will cut it into thin layers, the thickness of the stone layer is just enough to give priority to the bracelets, the rest will make other products to make full use of the stone block.
Preservation of Marble
Another thing to consider is how to preserve marble. The folk concept of "wearing marble on water for a long time" can be understood with the following meanings: sweat and friction against human skin for a long time and often can have a slight impact on the stone surface. glossier or slightly discolored, however it cannot increase the green color of marble.
Natural marble is a multi-mineral stone, so it has many pores and small cracks, if exposed to too high a temperature such as the heat of a jeweler's torch, it can cause the stone to crack and melt; When having to repair marble jewelry, remind the workers not to burn the stone with fire.
Natural light or strong light does not fade the natural marble color. With strong acids, marble can be slightly damaged.
Marble is very tough, difficult to crack when lightly bumped, but if it is hit hard, it can still cause the stone to crack and break. Most marble is usually coated with glue to protect the stone. However, the glue layer can be discolored, peeled off due to contact with cleaning chemicals, due to strong impact. When the glued marble is dirty, it is not recommended to wash it with an ultrasonic machine and a hot steamer because it is easy to loosen the glue. If the glue is peeling off, you should ask the marble craftsmen to polish it again.
If the stone is impregnated with color (artificial color), it is certain that the stone will gradually fade when worn, but long or fast depending on the quality of the color used for impregnating; Bad impregnated color only needs 1 month to fade, good color impregnated can take much longer but still hard to fade. When marble or marble jewelry is dirty, avoid using strong detergents, it is best to soak the product with warm soapy water and use a toothbrush to gently rub the lines, then use dry with a soft cloth, can be dried with a hair dryer, but not too close to the product and should not be dried for a long time.
Source: GIA - Gemological Institute of America and Golden Dragon Lab
