Chinese HPHT synthetic diamonds are included with rod-like, fine-point-like, tubular, and kite-like inclusions. The inclusions are characteristic of Chinese HPHT diamonds produced between 2017 and 2020. There are also some inclusions that cannot be seen. In the following paragraphs, we will examine the various types of inclusions in HPHT diamonds. We can explain hpht vs cvd diamonds. HPHT diamonds grow in a cuboctahedron shape and have 14 different growth directions, while a CVD diamond has a cubic shape and only one growth direction. This can sometimes cause a CVD diamond to show evidence of strains, but this is rare and only can be seen under extremely high magnification.
HPHT diamonds are synthetic diamonds grown in a metal catalyst. While diamonds grown in this process typically display no strain, metal particles can sometimes become trapped and put stress on the host diamond. Observable strain in HPH diamonds is generally seen only around inclusions. In the case of this synthetic diamond, this strain was observed around an internal inclusion that grew on the pavilion.
Observable strain in hpht diamonds may be determined through photoluminescence measurements. The shift in the QW emission wavelength was found to be 0.13 nm/K. In addition, capillary-bonded samples exhibited a redshift of 6 nm under optical pumping. These samples showed efficient heat transfer and low root-mean-square roughness.
Observable inclusions in diamonds are small, irregular structures inside the stone. These features do not affect the diamond’s clarity. When three or more of these inclusions are present, the diamond is called ‘cloud’. Cloud diamonds have multiple inclusions that look like a hazy smudge on the stone.
Observable inclusions are not visible to the naked eye, but they do appear under normal lighting conditions. Gemological laboratories use the “Pavilion View” method to see diamond inclusions. Regardless of whether the inclusions are visible or not, these stones are still considered good choices when combined with good color and cut. They are also usually well within the price range of most buyers.
Observable inclusions can appear on the top or inside of the diamond. These structures can be small, or they can be huge and cause problems. If these inclusions are enclosed, however, they do not affect the diamond’s durability.
Diamonds with VS2 clarity grade are among the most popular and offer a good balance of quality and price. These diamonds have small inclusions that are not visible to the naked eye. These inclusions are deemed minor and should not affect the appearance of the diamond.
Inclusions are visible when the diamond is magnified 10 times. This is the reason why VS2 diamonds are often referred to as eye-clean diamonds. However, this clarity grade is not always a desirable choice for a diamond. If you are not sure whether to purchase a diamond with VS2 or SI1 clarity, ask your jeweler about the diamond’s clarity grade.
Inclusions in VS2 diamonds are visible only under a 10x magnification. If you are able to see an inclusion, it will be difficult for you to judge whether it is a real diamond or a fake.
Inclusions in HPHT diamonds are typically black or silver and range in size from a few hundred to several microns. They can be rod-like or fine point-like in shape. The most common inclusion types are those associated with radial fractures.
These inclusions may be caused by solid minerals, gases, or native metals. In addition, trace elements, such as Ca, Na, Cl, Mg, P, and B, can also enter the diamond’s crystal lattice. For example, type IIa super-deep diamonds from the Juina Rio Soriso mine contain inclusions of Fe3C and Fe-Ni alloy.
The morphology of inclusions can help distinguish natural diamonds from HPHT IIa colorless diamonds. Raman spectroscopy is another method for distinguishing the two. Inclusions with characteristic PL peaks can be distinguished from those without. Using this method, the growth environment of a IIa diamond can be characterized.
Inclusions in Chinese hpht diamonds
Chinese HPHT diamonds often contain inclusions, which are tiny pieces of solid material. These pieces are typically silver or black in color, and can range in size from a few hundred to a few microns. These inclusions can vary in shape, too, from rod-like to fine point-like. Some examples of Chinese HPHT diamonds contain inclusions of the Fe-Ni alloy, pyrrhotite, or other trace elements.
These inclusions were created using a catalyst, which was typically iron, nickel, or cobalt, though other metals can also be used. The inclusions are created when the metal catalyst binds with the diamond’s atomic structure and becomes trapped in the diamond’s structure. They appear metallic in transmitted light, but are opaque when reflected. These inclusions can be isolated, or they can form boundaries between internal growth sectors.