Clarity

The clarity of colored gems is somewhat more difficult to grade than Diamonds. This is because of their type, color and often their source. Some colored gems are expected to be included to some degree. Emeralds, for example, are routinely included, and this is acceptable. A visibly included Diamond is not acceptable however. The difference is expectation. A Diamond is expected to be colorless and free of inclusions, an Emerald is not. Because of this difference, a slightly different Clarity Scale is used to grade colored gems. The basic terms describing clarity are the same; loupe clean, eye clean, slightly included, and so on. The difference is in describing the “type” of gem. The GIA (Gemological Institute of America) has divided colored gems into three types; Type 1, Type 2 and Type 3. These are described below.

 

Below are the definitions we use to describe the clarity of gems:
Internally Flawless (IF) – If a gem has been inspected under a microscope (40x or higher) and found to be free of inclusions.
Loupe Clean (LC) – Gems that are free from inclusions even under 10X loupe magnification.
Eye Clean (EC or VVS) – Gems that are clean to the naked eye. If there are inclusions, a loupe or other magnification may be needed to see them. Some gem sellers call this “Very Very Slightly Included” (VVS).
Very Slight Inclusion (VS) – These gems have some small inclusions, but they will not diminish the brilliance and beauty of the gem. Gemstones such as Prehnite or Friedelite, many not be included with visible particles, crystals, hairline fractures or bubbles, but may have a sleepy or soft and velvety quality. This means they are not eye clean but do appear to be free of specific inclusions. This “sleepiness” does not usually detract from the beauty of a gemstone and in the case of Prehnite, may add to its beauty. A good quality Prehnite may appear to “glow” with velvety color. Gemstones with a higher degree of “sleepiness” may also be called cloudy or Translucent.
Slight Inclusion (SI) – These gems have some inclusions visible to the naked eye but not to the extent of affecting the brilliance of the gem.
Moderate Inclusion (MI) – These gems have some inclusions visible to the naked eye and are ranked between SI and I.
Included (I) – These gems have some larger and/or many minor inclusions that somewhat diminish the brilliance of the gem. Some gem types, such as Bixbite and Emerald, are almost always included to some degree and not usually expected to be eye clean or better.
Transparent (Tp) – Transparent gems allow light to pass through them without diffusing the light.
Translucent (Tl) – Translucent gems allow light to pass through them, but the light is somewhat diffused.
Opaque (O) – Light can’t pass through the gem.

Clarity Types for Colored Gemstones using GIA Clarity Types

Type 1 – Gemstones that are normally found to be clean.
Examples: Amethyst, Aquamarine, Heliodor (yellow Beryl), Chrysoberyl (yellow), Citrine, Kunzite, Tanzanite, Topaz (blue).

Type 2 – Gemstones that normally may have a few inclusions.
Examples: Alexandrite, Andalusite, Iolite, Peridot, Rhodolite, Ruby, Sapphire, Spinel, Tourmaline, Tsavorite.

Type 3 – Gemstones that normally are not found to be clean.
Examples: Bixbite (red Beryl), Emerald.

GIA Clarity Grades for Colored Gemstones

abbreviation

clarity/inclusion description

VVS Type 1

minute to not detectable

VS Type 1

minor

SI1 Type 1

noticeable to obvious

SI2 Type 1

obvious to noticeable

I1 Type 1

moderate to prominent effect on appearance or durability

I2 Type 1

prominent to severe effect on appearance and durability

I3 Type 1

severe effect on appearance, transparency and durability

VVS Type 2

minor

VS Type 2

noticeable to obvious

SI1 Type 2

obvious to prominent

I1 Type 2

prominent to moderate effect on appearance or durability

I2 Type 2

prominent to severe effect on appearance and durability

I3 Type 2

severe effect on appearance, transparency and durability

VVS Type 3

minor to noticeable

VS Type 3

noticeable to obvious

SI1 Type 3

obvious

I1 Type 3

prominent to moderate effect on appearance or durability

I2 Type 3

prominent to severe effect on appearance and durability

I3 Type 3

severe effect on appearance, transparency and durability