Look beyond the grade alone
Clarity describes internal characteristics and surface features. Under GIA's natural-diamond system, the categories are FL, IF, VVS1-VVS2, VS1-VS2, SI1-SI2 and I1-I3; grading considers characteristics at 10× magnification.
What affects the result
The size, number, position, nature and visibility of characteristics all matter. Two stones with the same grade may look different to the unaided eye or have different considerations for setting and wear.
Define “eye-clean” before using it
“Eye-clean” is an informal description, not a laboratory grade. If used, ask about viewing distance, lighting and whether the stone was viewed loose or mounted. Do not treat it as a guarantee that every observer will see the same thing.
Make an informed comparison
Review the actual stone or suitable images and the available report. Ask whether any feature affects durability or requires a protective setting. Balance clarity with the other characteristics of the diamond and your budget.
Understand the details of your chosen diamond.