About Diamonds

The cut is the ability of the diamond to reflect light. It is what gives a diamond its fire and brilliance. A well cut or faceted diamond, regardless of its shape, scintillates with fire and light, offering the greatest brilliance and value.

Diamonds that are cut too deep or too shallow lose light that spills through the side or bottom. As a result, poorly cut stones will be less brilliant and beautiful, and certainly less valuable than well cut diamonds.

Pear:  A variation of the Brilliant cut, with 58 facets to only 56 facets. Shoulders should have a gently but distinctly rounded arch. Common length-to-width ratio: 1 to 1.50-1.75.

Oval:  A brilliant style of cutting very similar to a Round except it is elliptical. It was invented by Lazare Kaplan in the early 1960s.  Oval brilliant usually has 56 or 57 facets.  Beware of uneven or high shoulders (they should have a gently but distinctly rounded arch).  Typical length-to-width ratio: 1 to 1.30-1.65.

Marquise: This shape has a boat shaped girdle with 57 facets. The shape and placement of the facets is of the brilliant type.  Look for uneven "wings" or undefined points.  Typical length-to-width ratio: 1 to 1.75-2.25.

Emerald: It is usually rectangular but sometimes may be square, in which case it is known as a square emerald cut. It has rows (steps) of elongated facets on the crown and pavilion, parallel to the girdle, and with corner facets. The number of rows of elongated facets may vary, although the usual number is three on the crown and three on the pavilion.  Inclusions are slightly more visible in "step-cut" shapes relative to "brilliant styles. The beveled corners protect the stone and make it easier to set.  Typical length-to-width ratio: 1 to 1.30-1.70.

Princess (also the patented Quadrillion): Is a relatively new shape with at least 45 facets (no culet) normally close to a square shape (+ or - 10%), but may come in elongated versions.  Watch out for girdles which are extremely thin and thus prone to chipping.  Typical length-to-width ratio: 1 to 1.00-1.15.

Radiant: Patented cut with 70 facets (often confused with "cut corners Princess/Quadrillions").  Typical length-to-width ratio: 1 to 1.20-1.50

Heart: Look for uneven or flat "wings" or too shallow cleft. Typical length-to-width ratio: 1 to 0.90-1.10.

Diamonds are graded by color, starting at D and moving through the alphabet to Z. Most diamonds appear white, but virtually all display barely perceptible tints of color. Evaluating a diamond's color for grading purposes is done by measuring the degree to which a diamond approaches colorlessness. Diamonds graded D, E and F are colorless and more expensive because they are more rare. However, well-cut diamonds with good clarity of all color grades can be equally dazzling, as it is the combination of all the 4 C's that determines each diamond's unique beauty.

Virtually all natural diamonds contain identifying characteristics, yet many are invisible to the naked eye. Under the scrutiny of a 10x magnifying loupe of a microscope, natural phenomena called inclusions may be seen. These are nature's birthmarks, and may look like tiny crystals, clouds or feathers.
 

The above clarity grading scheme is in accordance with the GIA (Gemological Institute of America).  It is important to note that the GIA Grading system is not static, and has changed slowly over time.

Carat Weight

The term "carat" is a measurement of weight. Not to be confused with Karat, which is the purity of gold. Carat is also often confused with size even though it solely a measure of weight. One carat is equivalent to 200 milligrams. Five carats equals one gram. So, one carat is equal to 1/5 of a gram (or .2 grams). Also, keep in mind different gemstones are made up of different chemical elements, therefore they do not all weigh the same.