Last Updated on September 6, 2022
Deciding which clarity of a diamond is right for you depends on several factors.
VVS and SI diamonds are two common grades of diamonds that differ in quality and performance.
Here’s a look at what sets VVS and SI diamonds apart to help you better understand the differences between the two grades of diamonds.
What Are VVS Diamonds?
VVS diamonds are diamonds with a high clarity grade that fall between internally flawless (IF) diamonds and very slightly included (VS) diamonds on the Gemological Institute of America (GIA) clarity scale.
VVS diamonds have very few inclusions that are challenging to locate even under 10x magnification.
Inclusions found on a VVS diamond are less impactful than lower clarity diamonds and are unlikely to impact durability, appearance, or brilliance.
VVS diamonds are separated into two subcategories: VVS1 and VVS2.
These categories represent the subtle differences between how the inclusions in a diamond impact the durability, brilliance, and overall appearance of the diamond.
Both VVS1 and VVS2 diamonds look remarkably similar under high resolution and the subcategorization is determined by the analyzing gemologist.
Overall, there is not much visible difference between a VVS1 and VVS2 diamond.
What Are SI Diamonds?
SI diamonds are diamonds with a low clarity grade that falls between very slightly included (VS) diamonds and included (I) diamonds on the GIA clarity scale.
SI diamonds have many inclusions located on the table, pavilion, or crown of the diamond. Inclusions found on an SI diamond may impact the performance of the diamond and may reduce its brilliance and durability.
Like VVS diamonds, SI diamonds are separated into two subcategories: SI1 and SI2.
These categories represent small differences between the inclusions found within the diamond but don’t produce any meaningful differences in clarity.
SI1 and SI2 diamonds can have a variety of inclusions, including:
- Cavities
- Etch channels
- Needles
The shape, size, and amount of inclusions on an SI1 and SI2 diamond will vary and can include clusters of one type or a combination of inclusions spread across the diamond.
SI1 and SI2 designations are dependent on the gemologist.
Differences Between VVS and SI Diamonds
There are a handful of important differences to note between VVS and SI diamonds, including:
Number of Inclusions
The biggest difference between a VVS and SI diamond is the number of inclusions found on the diamond.
VVS diamonds will typically have fewer inclusions than SI diamonds.
Inclusions found on a VVS diamond will be invisible to the naked eye and will have a minimal impact on light performance, durability, and appearance.
Types of inclusions found on VVS diamonds may include:
- Feathers
- Pinpoints
- Indented naturals
In contrast, SI diamonds will have a larger number of inclusions that are visible to the naked eye.
Inclusions found in SI diamonds are plentiful and will typically include multiple types of inclusions, such as:
- Twinning wisps
- Feathers
- Black spots
These inclusions can distort light return, resulting in reduced brilliance and fire.
Because SI diamonds have more inclusions than VVS diamonds, VVS diamonds will always produce a higher brilliance than SI diamonds.
Overall Appearance
VVS diamonds are eye-clean.
While VVS diamonds contain inclusions, they appear flawless unless under magnification, making them the preferred option for center stones in engagement rings.
Conversely, SI diamonds are typically not eye-clean and contain inclusions that are visible to the naked eye.
SI diamonds over one carat are at increased risk of producing visible inclusions due to their large facets.
Because of this, SI diamonds are not typically recommended for center stones unless they have been viewed in person or under high resolution.
Price and Durability
VVS diamonds produce a flawless appearance and have a premium price.
On average, a VVS diamond will be 50-75% more expensive than an SI diamond.
However, this price is warranted because VVS diamonds have fewer inclusions than SI diamonds.
Because SI diamonds have numerous inclusions, they tend to be more prone to chipping and fracturing if dropped.
This is because a large number of inclusions found within an SI diamond weaken the structural integrity of the diamond.
If an inclusion is large or located on a delicate area of the diamond, it will be more susceptible to damage.
If considering an SI diamond, be sure to select an SI diamond with inclusions that have minimal impact on the durability of the diamond, such as:
- Pinpoints
- Twinning wisps
- Black spots
Additionally, choose an SI diamond with inclusions that aren’t located on delicate areas of the diamond, such as along a thin girdle.
