The cut of a diamond refers to its proportions. Cut is almost (with the exception of very poor clarity stones) totally responsible for fire and brilliance. Of the 4Cs, the cut is the only aspect over which man is the sole influence; the other three Cs are dictated mostly by nature. At Grissom’s we feel cut is the first and most important factor of quality.
Cut means much more than just a stone's shape although the two words are often confused. Shape varies by personal preference or nature’s demands while cut refers to the quality of the stone's reflective ability as well as its balance or symmetry. Whatever the shape, a well-cut diamond is better able to reflect light.
A diamond's ability to reflect light determines its display of fire and brilliance. Modern diamonds are generally 58 facet designs--a facet is a separate flat surface or plan. These facets follow a mathematical formula and are placed at precise angles in relation to each other. This balance will maximize the amount of light reflected back out of the diamond creating fire and brilliance, and off the stone's surface for luster.
Color grades rate or measure the amount or presence of body color in a diamond.
The absence of color in diamonds is very rare and highly prized. Since the late 90s, the demand for platinum has increased consumer demand for high color or colorless diamonds. Most diamonds mined in nature have traces of yellow, some brown or gray. Color is caused in diamonds by minute traces of other elements--for example, the presence of nitrogen will cause a yellowing while boron will cause a noticeable blue tint. Most diamonds in our inventory at Grissom’s will range from D (colorless) to K (very light yellow) D-E & F graded diamonds are called colorless and appear blue white. Many customers prefer (by their opinion of beauty) very slightly tinted colors (like I-J-or K); these stones cost less and still look white when mounted.
Diamonds come in all colors of the rainbow, even more shades than any colored gemstone. The most rare diamond colors are red, pink, and blue. Diamonds that display enough of a hue, or nuance of color to be desirable, are called fancy-colored diamonds. Yellow diamonds are most known to consumers as canary (a popular salesman’s slang) for light fancy to vivid fancy yellow. Brown--although it had it time of popularity in the eighties--is the least rare and is only requested occasionally. Strong brown stones have been over-produced from Australian mines and even have been poked fun of in movies and commercials in recent years.
Color is an important factor to beauty, rarity, and value because it is something a consumer can see without the aid of equipment. It is vital to buy a color you are happy with as you will notice the color only secondly to the fire in a diamond.
Clarity grade refer to the degree to which the diamond is free of inclusions and blemishes. Nature produces very few things that man calls perfect. Perfect or Flawless in diamond grading means a pure clean stone under 10x magnification. 10x is the worldwide industry standard for diamond grading. Most diamonds have internal flaws known as inclusions, and external characteristics called blemishes. These clarity characteristics are evaluated under 10X magnification, by trained diamond graders, based on the number, nature, size, location and color of each characteristic. Clarity characteristics are also used to distinguish one diamond from another. A diamond's inclusions are often used as identification as they make each diamond one-of-a-kind. Flawless diamonds are extremely rare and command the highest prices, but finding a diamond with minute inclusions can reduce the cost of the stone without detracting from its beauty or durability.
Carat is a weight measurement exclusive to the diamond and gem industry it was adopted in the United States in 1913. A metric Carat is equal to .200 grams or 200 milligrams. A carat is subdivided by 100 points (think of a point as one percent of a carat). Carat, abbreviated as (ct), is often confused with Karat (kt); both are pronounced the same, but Karat is a US gold purity rating. All gems do not look the same size at a given Carat depending on depth of cut and specific gravity of a given gem type. Sapphire and Ruby (corundum) have higher specific gravities making them weigh about 30% more per volume or look 30% smaller.
Many times a diamond that sounds like a bargain will be cut much too deeply giving weight without adding to the visual size and costing the stone fire, brilliance, and luster. Very deeply cut stones may also be more difficult to set in an appealing manner -- so remember, a carat is not just a carat. Use the diagram below to help understand proper measurements based on carat for the various shapes.