Few things in nature are
absolutely perfect. That is as true of
diamonds as anything else.
Diamonds have internal features called inclusions, and surface irregularities called blemishes. The clarity characteristic of a diamond is determined by the relative absence of inclusions and blemishes.
The Federal Trade Commission guidelines prohibit use of the term "flawless" or "perfect" to describe any diamond that doesn't fit the description.
Diamond clarity characteristics are defined as follows:
- Internally Flawless (IF): No inclusions and only minor blemishes visible under 10x magnification.
- Very Slightly Included (VVS1-VVS2): Minute inclusions that are extremely difficult (VVS1) or very
difficult (VVS2) to see under 10 x magnification.
- Very Slightly Included (VS1-VS2): Minor inclusions that are fairly difficult (VS1) or fairly easy (VS2)
to see under 10x magnification.
- Slightly Included (SI1-SI2-SI3): Noticeable inclusions that are easy (SI1) or very easy (SI2) to see
under 10x magnification. A small percentage of diamonds have inclusions that can be seen
without magnification (SI3), but have little effect on appearance.
- Included (I1-I2-I3): Significant inclusions that are usually visible (I1), easily visible (I2), or obvious
(I3) without magnification. I2 diamonds may affect durability. I3 inclusions pose a definite threat to
a diamond's lasting power.