Jade Revealed: Why Does Jadeite Turn Yellower the Longer You Wear It?
Jadeite, as a precious gemstone, has been revered since ancient times. Many people wear jadeite with the hope that it will bring good fortune and health, and some even believe it can "nourish" its wearer. However, not all jadeite becomes more beautiful over time some may turn yellow and lose their original luster. So, why does jadeite become yellower the longer it is worn? The reasons behind this phenomenon are multifaceted, involving factors such as the quality of the jadeite, its processing methods, and environmental conditions during wear.
1. When You Encounter "Cosmetically Enhanced" Jadeite
In the jadeite market, "Type A" jadeite represents natural, chemically untreated jadeite, while "Type B" and "Type C" refer to jadeite that has undergone chemical treatments. Particularly with Type B and Type C jadeite, their relatively low prices often attract many consumers. However, precisely because of this, many people may not realize when purchasing jadeite that these pieces might have undergone chemical treatments such as "acid cleaning" or "coating," which can lead to discoloration and yellowing after prolonged wear.
Type B jadeite refers to jadeite that has undergone chemical treatments such as acid washing, passivation, and impurity removal. The inherent texture of such jadeite tends to be relatively loose. Although acid washing makes the surface appear cleaner and smoother, it leaves traces of chemical treatment inside the jadeite. To compensate for the structural flaws of the jadeite, merchants often use fillers like resin to fill its gaps. This enhances the surface appearance and color vibrancy of the jadeite. However, over time, the resin and other fillers gradually fade, causing the jadeite to turn yellow and lose its luster. Type C jadeite, on the other hand, is built upon Type B jadeite and further enhanced through dyeing to intensify its color brightness. While such jadeite may appear vibrant in color, prolonged wear leads to the fading and peeling of the dyes, resulting in uneven color changes in the jadeite, which may turn yellow or dull.
Some jadeite pieces are further enhanced in appearance through coating treatment. This process forms a thin protective film on the surface of the jadeite, giving it a brighter luster and more vibrant color. However, as the coated jadeite is worn over time, this protective film may gradually peel off or deteriorate, leading to yellowing and dullness on the surface. This phenomenon typically occurs with Type B or Type C jadeite, especially those that have undergone such treatments, making them more prone to color fading and yellowing during wear.
If you notice your jadeite turning yellow or losing its luster, the first step is to determine whether it is Type B or Type C jadeite, which typically requires professional appraisal. If the purchased jadeite has undergone acid treatment or coating, it is advisable to stop wearing it. This type of jadeite not only fails to provide any beneficial effects but may also pose potential risks to your health.
2. Unavoidable Natural Oxidation
As a natural mineral, the surface of jadeite undergoes changes over time with prolonged wear. Oxidation is a common phenomenon in jadeite, typically manifested as a loss of luster, dulling of color, or even yellowing of the surface. Unlike the transformation or "zhong" variation in jadeite, this oxidation primarily occurs on the surface layer and is generally repairable.
The oxidation of jadeite occurs primarily because its surface is exposed to environmental factors such as oxygen and moisture in the air. Oxygen in the air reacts with the mineral components on the surface of jadeite, causing it to gradually lose its luster and its color to become dull. Additionally, substances such as oils, dust, and chemicals on the surface of jadeite can also affect its appearance, leading to gradual yellowing. When jadeite is worn, oils secreted by the human body, sweat, and acidic substances on the skin can react with its surface. Over time, this accumulation can result in oxidation. Especially during activities such as exercise, housework, or cooking, jadeite is more likely to come into contact with sweat and chemicals, thereby accelerating the oxidation process.
If the oxidation of jadeite occurs only on the surface and does not penetrate its internal structure, it can be repaired through professional cleaning and maintenance methods. Common restoration techniques include taking the jadeite to a professional jewelry store for cleaning, where specialized tools and cleaning agents are used to remove surface dirt and oxides. Afterwards, waxing and polishing are applied to restore the jadeite’s luster and color. For jadeite with mild surface oxidation, the restoration results are generally good. After treatment, the jadeite’s shine and color can be brought back to a state close to its original appearance. However, if the jadeite has already undergone severe oxidation, the restoration effectiveness may be reduced, and the surface may still exhibit slight dullness or yellowing.
To prevent jadeite from oxidizing, it is advisable to avoid contact with sweat, oils, chemicals, and similar substances while wearing it. During activities such as housework, exercise, or bathing, it is best to remove the jadeite. Additionally, regularly cleaning and maintaining jadeite is an essential measure to prevent oxidation. Gently rinsing jadeite with clean water and drying it with a soft cloth can effectively remove dust and oils from its surface, helping to prevent oxidation and discoloration.
3. The "Transformation" of Jadeite Itself
Prolonged wearing of jadeite may gradually cause it to turn yellow, which could indicate a process known as "zhong transformation" (种变化). This transformation involves more than just surface discoloration; it is, in fact, a change in the internal structure of the jadeite. Such changes typically occur due to loose crystal structures in the jadeite, leading to moisture loss, intrusion of oils and dust, or oxidation triggered by contact with chemical substances.
The phenomenon of jadeite "zhong transformation" typically occurs in "young zhong" (嫩种) jadeite. "Young zhong" refers to jadeite with a relatively loose internal granular structure, where crystalline water is prone to evaporation. Over time, the loss of moisture causes the jadeite to lose its original luster, eventually becoming dry, dull, and even gradually yellowing. In contrast, "old zhong" (老种) jadeite, due to its dense crystalline structure and high density, exhibits stronger oxidation resistance and durability, making it less susceptible to such transformation. Young zhong jadeite is easily influenced by external factors, leading to changes in its texture and color, whereas old zhong jadeite, with its stable structure and fine grains, generally does not undergo similar changes. The manifestation of zhong-transformed jadeite usually begins at the edges, gradually turning yellow and dry, eventually affecting the color of the entire piece.
Once jadeite undergoes zhong transformation, the changes in its internal structure are irreversible. The color of transformed jadeite gradually shifts from green to yellow or brown, and its surface becomes dry and loses its luster. Despite this, transformed jadeite is not equivalent to waste, it still retains the fundamental properties of jadeite, though its appearance is no longer as pristine. If your jadeite has undergone transformation, there is no need to discard it immediately. You can keep it as a unique memento or add it to a collection. For jadeite with mild transformation, it can also be sent to professional cleaning and polishing shops. After treatment, some degree of luster and aesthetic appeal can be restored, though the results may be limited. Importantly, transformed jadeite still retains practical value and poses no harm to the wearer's health.
Rather than trying to salvage jadeite that has already undergone transformation, it is wiser to prevent risks at the source. The "zhong" (种) of jadeite directly determines the stability of its structure and serves as the fundamental basis for judging whether it is prone to transformation. When selecting jadeite, special caution should be exercised with the following two types that are susceptible to transformation:
Young Zhong Jadeite: This refers to jadeite with a loose internal structure and easily evaporable crystalline water. Due to the large gaps between its crystals, this type of jadeite tends to gradually dry out and turn yellow as moisture is lost, such as the commonly seen "horse tooth" variety. Although the texture may appear fine to the naked eye, its inherently loose structure makes it more vulnerable to environmental influences and prone to transformation.
New Pit Jadeite: This refers to jadeite that has been mined recently and has not undergone sufficient geological sedimentation. Its structure is often not dense enough, and its surface is frequently waxed to enhance its luster. Over time with wear, the wax layer gradually wears off, revealing the originally concealed rough texture and unstable structure, which can cause the jadeite to lose its luster or even turn yellow. It is recommended to prioritize jadeite from old pits that have undergone full natural sedimentation.