The difference between natural jadeite black cotton and Longserving Lab-Grown jadeite white cotton
The difference between natural jadeite black cotton and Longserving Lab-Grown jadeite white cotton
Talking about the "cotton" of jadeite
"No jade without cotton." In high-quality jadeite, from slightly translucent to very watery, white specks or flocs are common, as are black ones. We call these "cottons." Simply put, they resemble cotton wool. Jadeite is a polycrystalline material, and cotton wool is composed of albite. It is visible to the naked eye in icy jadeite. Even finished jadeite with lower water content may contain albite, but its opacity makes it less noticeable. Almost all jadeite has cotton wool. Opaque finished jadeite also has albite, but its opacity makes it less visible to the naked eye. The presence of cotton wool in finished jadeite often detracts from its beauty and value. Excessive cotton wool in icy and glassy jadeite, in particular, degrades its value. With expert craftsmanship, however, this can be transformed into something truly extraordinary. For example, the numerous cotton-like specks on icy jadeite can be designed to resemble dancing snowflakes; the cotton wool in spring-colored jadeite can be designed to resemble magnolias, clouds, or even starry sky.
Of course, there are also jade products known for their cottoniness, such as the "Mu" variety. Mu" is famous for its snowflake-like cottoniness. The cottoniness within jade can be seen under side or bottom lighting, appearing transparent or translucent. This cottoniness is mostly caused by light reflection between the intergranular spaces, cracks, and inclusions within the jadeite grains, also known as the "intergranular optical effect." The cottoniness within jade obscures the color of the jade, preventing it from penetrating. The more cottoniness there is, the lower the jade's light transmittance, which in turn affects the color's visibility.
Black spots, black threads, and black patches in jade often appear as dots, patches, threads, and bands. These different forms of black can vary significantly in their mineral composition. Black spots are often remnants of chromite. Cottoniness affects the reflection of jade's color within the jade's flesh, specifically the diffusion of the jade's color or color roots within the jade. If the cottoniness within jade is abundant and concentrated, it will affect the color's diffusion.
Under natural light, the cottoniness within jade with good water quality and high transparency, such as ice-type jade, is particularly noticeable. The presence of asbestos will also affect the quality of jade and its texture. Therefore, when purchasing jade, you need to consider the effect of cotton on the quality of jadeite.
Difference between natural jadeite black cotton and synthetic jadeite white cotton
Chromium does not exist in natural minerals. It is contained in chromite and extracted from chromite. Therefore, pure chromium does not exist in nature. Chromium and iron are mixed together. In natural jadeite, the green color must originate from the chromite itself. We know that green is the primary color of imperial green. Iron contributes to a darker color, which is why you see black spots and black cotton. Black cotton is mostly iron. Synthetic jadeite, however, has already been refined, and the iron ratio can be controlled during the synthesis process. Therefore, synthetic jadeite does not have black spots. However, the white cotton in synthetic jadeite is a natural mineral cotton. Natural mineral cotton is a mixed crystal of sodium aluminum sodium chrome pyroxene. Sodium aluminum pyroxene is white, and sodium chrome pyroxene is green.
When it crystallizes in the laboratory, natural selection occurs, resulting in a mixed crystal of sodium chrome pyroxene and sodium aluminum pyroxene. Sodium aluminum pyroxene is what we call white crystals, but if the crystals are uniform, this is not a problem. Natural jade differs from synthetic jade. Synthetic jade doesn't have black spots or black cotton, but it does have white cotton, just like natural jade. If a bit of sodium aluminum is mixed into a piece of sodium chrome pyroxene, it will appear white, a lighter color.
If it's affected by chromium, it becomes chrome pyroxene, which is green. Chromium then turns green. If it's contaminated by iron, it becomes iron pyroxene, and then sodium iron pyroxene. Iron is the most abundant mineral in nature. When magma in the seafloor crust cools and creates cracks under high pressure, elements like sodium, chrome, and iron in the seawater seep into the pyroxene mineral, forming sodium pyroxene. Why does sodium pyroxene have green bands? It's because iron or chromium seeps into these cracks, creating the green bands in jade. These green bands, when encased by metamorphic rocks, form a green band. Because iron is the most abundant mineral in nature, iron has the highest specific gravity, which is why natural jade often has black spots. So, if there's no iron, it's pure nautilus. Because its color is lighter, it appears as white cotton in jade. Sodium chrome pyroxene creates a more vibrant imperial green jadeite color, while sodium iron pyroxene is a darker green, or even with black cotton.
The white cotton in synthetic jade is due to the fact that the mineral is controlled in the laboratory. We minimize the iron content to prevent black spots and maintain crystal purity. Synthetic jadeite chrome pyroxene becomes the main component, and it's a mixed crystal of sodium chrome pyroxene and sodium aluminum pyroxene, just like the natural composition. However, the sodium aluminum pyroxene is lighter in color, resulting in the appearance of white cotton in the gem.
Synthetic jade is more likely to have lighter white cotton, but no black spots. Because the iron content is lower, unlike natural minerals, this is the biggest difference between synthetic and natural jade. Natural jade does have white cotton, of course, but it's not without it. Without cotton, it's not jade. If it's completely flawless, with no black spots or white cotton, it's definitely dyed agate or quartz.
Case sharing: The one on the left middle finger is a Lab-Grown jadeite. The one on the right is her natural jadeite with obvious black cotton.
