The clarity of a diamond depends on how “clear” or “clean” it is — how free it is of blemishes and inclusions when viewed with the naked eye and with a 10X loupe or magnifier. Let’s define our terms.
BLEMISHES: Imperfections on the outside of a diamond
Chip: A little piece missing, caused by wear or the cutting process.
Scratch: A line or abrasion.
Fracture: A crack on the diamond’s surface.
Polishing lines: Fine lines on the stone’s surface formed during the polishing stage.
Natural: An unpolished part of the diamond.
Extra facets: Additional polished surfaces that shouldn’t be there and spoil the symmetry of a diamond.
Bearding: Very small fractures on an edge of the diamond.
INCLUSIONS: Imperfections inside a diamond.
Carbon: Black spots inside a stone.
Feather: Internal cracking.
Crystal: White spots inside a stone.
Pinpoint: Tiny spots, smaller than a crystal.
Cloud: A group of pinpoints, which may give the impression of a single large inclusion.
Loupe: (pronounced loop) a small magnifying glass used to view gemstones. Any good jeweler will let you use one, and show you how. They should be 10X, or 10-power magnification, and the housing around the lens should be black so as not to distort the color of the stone. The Federal Trade Commission requires diamond grading to be done with a 10X magnifier, and any flaw that can’t be seen under 10X magnification is considered nonexistent.
Here are the CLARITY GRADES OF DIAMONDS, as established by the Gemological Institute of America (GIA), and their corresponding definitions using hard-grading standards:
FLAWLESS: Free from inclusions and blemishes when viewed under 10X magnification. Very rare and very expensive.
INTERNALLY FLAWLESS: Free from inclusions; may have slight blemishes when viewed under 10X magnification. Also very rare and very expensive.
VVS1 AND VVS2 (VERY, VERY SLIGHTLY INCLUDED): Has minute inclusions or blemishes the size of a pinpoint when viewed under 10X magnification. Rare and expensive.
VS1 AND VS2 (VERY SLIGHTLY INCLUDED): Has inclusions or blemishes smaller than a grain of salt when viewed under 10X magnification. No carbon, fractures or breaks. High quality.
SI1 (SLIGHTLY INCLUDED): Has inclusions or blemishes larger than a grain of salt when viewed under 10X magnification, and these inclusions can be carbon or fractures. Almost all SI1 diamonds are eye-clean, which means the flaws can’t be seen with the naked eye. Good quality.
SI2 (SLIGHTLY INCLUDED): Has inclusions or blemishes larger than a grain of salt when viewed under 10X magnification, and some of these flaws may be visible to the naked eye. Borderline diamond.
I1 (IMPERFECT): Has inclusions and blemishes visible to the naked eye. Commercial grade. Not my taste!
I2 (IMPERFECT): Has inclusions and blemishes visible to the naked eye that can make as much as one-fourth of the diamond appear cloudy and lifeless. Same as above.
I3 (IMPERFECT): Has many, many inclusions and blemishes visible to the naked eye. Not a pretty diamond. Very little luster or sparkle. Bottom of the barrel.
FRED’S ADVICE: Aim for an VS2 diamond. Many people unwittingly buy SI1 and SI2 stones, but if you shop carefully you can buy an VS2 stone for the same price that most SI2 stones are sold for.
by Fred Cuellar, author of the best-selling book “How to Buy a Diamond.” More questions? Ask the Diamond Guy®