Evaluating Colored Gemstone Clarity

Clarity grading involves examining a gem’s transparency, inclusions, and blemishes.

The Gemological Institute of America (GIA) has devised a clarity grading system that, first, groups colored gemstones into three types:

GIA Clarity Types

I
Usually eye clean
II
Usually included
III
Almost always included
Aquamarine
Chrysoberyl, yellow and green
Heliodor
Morganite
Smoky Quartz
Spodumene, all
Tanzanite
Tourmaline, green
Zircon, blue
Andalusite
Alexandrite
Corundum, all (ruby, sapphire)
Garnet, all
Iolite
Peridot
Quartz (amethyst, citrine, ametrine)
Spinel, all
Tourmaline, all but green, red and watermelon
Zircon, all but blue and colorless
Emerald
Tourmaline, red and watermelon

Clarity Grades

GIA clarity grades have different meanings, depending on the gem type.

I II III
VVS Minute inclusions, difficult to see under 10X. Eye clean. Minor inclusions, somewhat easy to see with 10X. Usually eye clean. Noticeable inclusions under 10X. Usually eye clean.
VS Minor inclusions, somewhat easy to see with 10X. Usually eye clean. Noticeable inclusions under 10X. May be eye visible. Obvious inclusions with 10X. May be eye visible.
SI1 Easily noticeable with 10X. Slightly visible to the unaided eye. Usually low relief. Obvious inclusions, large or numerous under 10X. Apparent to unaided