What Are SI Diamonds?
SI diamonds are a category of diamonds that contain inclusions within their internal structure. To the naked eye, these stones may be what jewelers call 'eye clean', meaning that the inclusions present are not visible to the naked eye. However, inclusions are certainly present and can affect the brilliance of the stone. Therefore, it is important to consider other qualities that will enhance the brilliance of the diamond, these being cut and colour.
Is SI a Quality Diamond?
An SI diamond is a quality diamond. As a clarity rating, SI, which means "slightly included," is considered an excellent gemstone with minimal inclusions. All diamonds have minor flaws, including higher clarity diamonds that are graded as flawless. Choosing a SI clarity diamond that has a good combination of carat, cut, and color is an excellent choice. What Does Diamond Clarity SI Mean?
Clarity grades range from Very Included to Flawless and reflect whether a diamond has any visible flaws.
In nature, diamonds are formed from carbon deposits exposed to high temperatures and pressures. Small impurities can cause defects in this structure as atoms rearrange themselves to form the crystalline structure characteristic of the diamond lattice.
After looking for visible inclusions and flaws at 10x magnification, experts will decide which of six clarity categories the diamond falls into:
If the stone has no visible inclusions or flaws that can be detected at 10x magnification, it is a flawless diamond.
Stones with slight flaws but no inclusions are Internally Flawless or Flawless.
A diamond can be Very, Very Slightly Including if the inclusions are hard to see but still present. There are two subcategories, VVS1 and VVS2, depending on how visible the inclusions are.
A diamond with Very Few Inclusions has small inclusions. A VS2 diamond has slightly more visible inclusions than a VS1
If inclusions and flaws are more noticeable, an expert will likely grade a diamond as Slightly Including. Depending on how visible the flaws are, a diamond can be SI1 or SI2.
Finally, diamonds with inclusions are included, which affect the transparency and brilliance of the stone. There are three subcategories for these stones: I1, I2 and I3.
SI diamonds are less valuable than stones with better clarity grades, but unless you look at a stone closely or use magnification, inclusions, flaws and other imperfections remain difficult to detect.
