Beautiful and rare, diamonds are desired for their sparkle and message of love. When you buy a diamond there are four points that you should consider, CUT, COLOR, CLARITY, and CARAT WEIGHT, collectively known as the Four C's.
Cut refers to the symmetry and proportions of the stone; it is what gives the diamond its sparkle. There are many diamond shapes to choose from. Whatever shape and quality you prefer, a Laboratory Report should be a requirement for your engagement ring or any significant diamond purchase. The cut of a diamond refers to its proportions. Of the 4C's, the cut is the aspect most directly influenced by man. The other three are dictated by nature.
Quite often the cut of a diamond is confused with its shape. Diamonds are cut into various shapes depending upon the original form of the uncut diamond, which is referred to as rough. 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. Diamonds are usually cut with 58 facets, or separate flat surfaces. These facets follow a mathematical formula and are placed at precise angles in relation to each other. This relationship is designed to maximize the amount of light reflected through the diamond and to increase its beauty.
The most desirable diamonds are colorless. The best color is D, which is almost clear white; the color scale descends from there through the alphabet toward Z, moving further away from colorless toward yellow or brown tints. The best color is no color. Diamonds allow light to be reflected and dispersed as a rainbow of color. This light dispersion, or color flash, has no effect on the technical grading of color. The absolute finest colorless stone carries a D rating, descending through each letter of the alphabet to Z, designating a diamond of light yellow, brown, or gray. This body color may be caused by the presence of trace elements, such as nitrogen, within the atomic framework of the carbon crystal. These trace elements are so minute that they are scientifically measured in parts per million (ppm). As the body color becomes more intense, the grade for color descends the scale. These gradations are so minute and precise that discerning a single grade (even by an expert) under less than ideal laboratory conditions is extremely difficult. It is always best to compare diamonds graded by either the Gemological Institute of America (GIA) or the American Gem Society (AGS) for accurate color grading. When directly comparing diamonds for color, most consumers are unable to detect a difference unless they are at least two or three color grades apart. We recommend selecting a diamond with a color grade of K or better.
It is often surprising to learn that diamonds also occur by rare accidents of nature in shades of pink, blue, green, amber, or even red. These rarely occurring colors are referred to as fancies and are evaluated by a different set of color standards. These standards take into consideration various factors such as hue and saturation. Fancy colored diamonds are the most expensive because of their extreme rarity. Some fancy colors can cost hundreds of thousands of dollars for diamonds of one carat or less!
Fluorescence is not directly related to a diamond's color. This separate characteristic refers to the diamond's ability to fluoresce under ultraviolet (UV) light. Our sun emits some UV light, but it is usually not great enough to detect fluorescence. The most common source of UV is a black light. When exposed to UV light, many diamonds will give off a distinctive glowing blue coloration. Although fluorescence may be displayed in various colors, blue is the most common in diamonds. The fluorescence of a diamond is defined by its intensity as either None, Faint, Medium, Strong, or Very Strong. Although fluorescence is a characteristic that can be measured, it is seldom an issue when selecting a diamond.
Diamonds have small imperfections in them known as inclusions; the fewer inclusions, the more valuable the stone. Almost all diamonds contain very tiny natural birthmarks known as inclusions. To determine a diamond's clarity, an expert views it under 10 power magnification. In addition to internal inclusions, surface irregularities are referred to as blemishes. These two categories of imperfections-inclusions (internal) and blemishes (external)-make up clarity.
The fewer the imperfections, the rarer and more valuable the diamond. Many inclusions are not discernable to the naked eye and require magnification to become apparent. A laboratory-certified clarity rating of SI2 represents the point at which inclusions are technically not apparent to the average naked eye.
Contrary to popular belief, higher clarity does not always mean more beautiful. If the inclusions are not visible to the naked eye, a higher clarity does not really improve the appearance of a diamond but rather the rarity and price. A higher clarity is more desirable and valuable, but knowing that you have selected the right clarity for the right reasons is most important. We recommend a clarity of SI2 or better.
Clarity is graded using a very precise and complex method of evaluating the size, location, and visibility of inclusions. The diagrams to the right show a top view of a round diamond. The inclusions, shown in red, are an approximate sample for each clarity rating. The plotted inclusions may not be actual size for display purposes. Remember, the inclusions depicted in red are not visible to the average naked eye until the I1-I3 clarities. Below is the technical clarity scale with a description of each term.
The Carat Weight is the size of the stone. The word carat comes from the carob seeds that were used to balance scales in ancient times. Most people compare carat weight to size. The larger the diamond the more it weighs. The weight of a diamond is expressed in carats. The word carat originated from the carob tree or Ceratonia siliqua. The tiny seeds of this tree are well known for their uniformity and consistent weight. Traditionally diamonds and gemstones were weighed against these seeds until the system was standardized, and one carat was fixed at 0.2 grams. One carat is divided into 100 points. A diamond weighing one quarter of a carat can also be described as weighing 25 points or 0.25 carats. Points are generally not used to describe weights over one carat. Here are some examples of different weights for round diamonds and their corresponding sizes. These may not be actual size due to your monitor. The approximate girdle diameter is displayed in millimeters.
The rarity of a diamond is greatly affected by its size. The rarity of a 1.00 carat diamond is much greater than twice that of a .50 carat. Although it only weighs twice as much, the 1.00 carat is statistically much more difficult (rare) to mine than the .50 carat. For an easy comparison of price and size, see the table below. Prices are approximate and based upon D Color, internally flawless, excellent cut.