Picking the Perfect Diamond

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Ask the Expert:
How to Pick the Perfect Diamond
By: Frederick Jerantdiamond_shapes_allweb


If it’s true that “diamonds are a girl’s best friend,” then it’s equally true you should pick them the way you pick human friends – carefully. But buying a diamond can be challenging, especially when the seller tosses around terms you don’t understand.

Fortunately, Sarah H. Schaffer, general manager and president of Northampton Coin and Jewelry, gave me a crash course on the “Five Cs of Diamonds” – basic information that can guide you as you search for the gem of your dreams.

COLOR: Colorless diamonds are graded D (the rarest) to F; nearly-colorless, G to J; the rest show increasing evidence of color (usually yellow), to grade Z. Beyond grade Z, you are dealing with “fancy color” diamonds.

CLARITY:  The relative absence of minute inclusions – spots, cloudy areas, internal fractures — which are present in all but the finest diamonds. This “C” ranges from FL –IF (flawless to internally flawless) down through VVS1-2, VS1-2, SI1-2, I1 and I2-3. The number of inclusions, their size and darkness, and locations within the stone influence the diamond’s clarity grade.

CARAT WEIGHT: “Karat” is an indicator of gold purity, but “carat” is the physical weight of the stone. Naturally, heavier stones are more expensive. And stones have depth and width – so the crown of a 1-carat diamond isn’t twice as big as that of a 0.5 carat stone.

CUT: indicates the diamond cutter’s skill. The cut, polish and alignment of facets should produce dazzling displays of reflected light. Lesser-cut stones will look relatively dull.

The old definition of “cut” meant a diamond’s shape – round, oval, or princess, for examples. Shapes fall in and out of favor, and so can impact a diamond’s value over time.  Shaffer says the traditional round-brilliant cut is the only shape that has consistently maintained its value.

CERTIFICATION: if a diamond is certified by the Gemological Institute of America (GIA) or another impartial body, you can be sure the stone’s other “Cs” are exactly as presented by the merchant.  It doesn’t validate a stone’s price (and shouldn’t include one); rather, it’s an independent and objective assessment of its qualities.

How does all of this knowledge translate to value? “Assuming other things are equal, you can get the most for your money by aiming for the middle range,” Schaffer says. “Look in the color grades of G, H and I, and clarity of VS or SI. The differences between these and higher-graded stones can be subtle, and most people won’t see the difference. And a top-of-the-line 2-carat round could range up to $50,000; you could pay 50% less for a middle-quality diamond.”

Remember, also, to be flexible. Larger stones can be more affordable if you’re willing to accept a somewhat lower grade in color or clarity.