A diamond’s clarity refers to the presence of identifying characteristics on and within the diamond. While most of these clarity characteristics are inherent qualities of the rough diamond and have been present since the earliest stages of the diamond crystal’s growth below ground, a few clarity flaws are actually a result of the harsh stress that a diamond undergoes during the cutting process itself. If you think about the incredible amount of pressure it takes to create a diamond, it’s no surprise that many diamonds have clarity inclusions — scratches, blemishes, air bubbles or non-diamond mineral material — on their surface or inside. Diamonds with no or few inclusions and blemishes are more highly valued than those with less clarity, not just because they are more pleasing to the eye, but also because they are very rare.
Diamonds are graded for clarity under 10x loupe magnification. Clarity grades range from Internally Flawless, diamonds which are completely free of blemishes and inclusions even under 10x magnification, to Imperfect 3, diamonds which possess large, heavy blemishes and inclusions that are visible to the naked eye.
FL: Completely flawless
IF: Internally flawless; only external flaws are present, which can be removed by further polishing the stone
VVS1 – VVS2: Only an expert can detect flaws with a 10X microscope. By definition, if an expert can see a flaw from the top of the diamond, it is a VVS2. Otherwise, if an expert can only detect flaws when viewing the bottom of the stone, then it is a VVS1
VS1 – VS2: You can see flaws with a 10X microscope, but it takes a long time (more than about 10 seconds)
SI1 – SI2: You can see flaws with a 10X microscope
I1 – I3: You can see flaws with the naked eye.