Diamonds
Extremely rare, unalterable, the hardest material known and brighter than a thousand stars, the diamond is the most prestigious of all precious stones. Diamonds are the crystal essence of emotion. They capture the light and release it, one facet at a time. The diamond’s value is assessed in accordance with four factors, known as the “4Cs”: cut, color, clarity and carat.
Cut
A diamond's cut is considered to be the most important of the four Cs. It is important to understand how a diamond's proportions and the relationship between them affect its brilliance, fire, and scintillation.
Ideal Cut Diamond
Cut, more than any other quality aspect, gives the diamond its sparkle. A diamond gets its brilliance and scintillation by cutting and polishing the diamond facets to allow the maximum amount of light that enters through its top to be reflected and dispersed back. When all the angles are correct, the light that enters is dispersed back through the diamonds top facets.
Inferior Cut Diamonds
Most diamonds are "spread" in their cutting to retain maximum weight from the original rough. A heavier diamond will result, but so does a dramatic sacrifice of potential fire and brilliance. The width and depth have the greatest effect on how light travels within the diamond, and how it exits in the form of brilliance.
"Fisheye" - Shallow Cut Diamond
When a diamond is cut too shallow, light leaks out of the bottom, brilliance is lost and the diamond appears watery, glassy and dark. A diamond with these characteristics is referred to as a "fisheye".
"Nailhed" - Deep Cut Diamond
When a diamond is cut too deep, light leaks out of the sides, brilliance is lost and the center of the diamond will appear to be dark. A diamond with these characteristics is referred to as a "nailhead".
Color
Diamond color is one of the most important factors to consider, as it is noticeable to the "naked" eye. A diamond's color is graded by GIA on an alphabetical scale from D-Z, with D being absolutely colorless and Z being light yellow. Beyond "Z", a diamond is considered to be a "Fancy" color. Although many diamonds appear to be colorless, the many of them have at least a hint of body color.
GIA and AGS Color Grading Scale:
Diamond Proportions
Experts express differing opinions on the best table size (the diameter of the largest facet on the top of the stone) and the best depth for a diamond, because these factors alone are not sufficient to accurately judge its cut.
Other factors - crown angle, girdle thickness, pavilion depth-percentage (the ratio of depth to girdle diameter), culet size, polish and symmetry - also play a role in judging a diamond's overall cut quality.
A diamond's cut is graded by several measurements. Its depth percentage (a measurement of the height vs. the width of the stone) and its table percentage (a measurement of the diameter of the top facet of the stone vs. the stone's average width) are two key factors in determining the quality of a diamond's cut.
Polish & Symmetry
Although polish and symmetry are graded under 10X magnification they can both have an effect on the overall appearance of a diamond. Polish refers to the quality of the diamond's surface and includes such features as nicks, polish lines and abrasions. Symmetry refers to the exactitude of the shape and alignment of the facets.
Some of the symmetry characteristics of round diamonds are listed below:
Diamond color has a significant impact on its value. To ensure the highest quality diamonds for your selection we carry diamonds in the color range from D-K only. When buying a diamond, take into consideration that it is often very difficult to detect the difference between a colorless diamond (D-F) and a near colorless diamond (G-J), especially when it is mounted in jewelry. Diamonds with a K-Z color grade usually have yellow shading that can be detected by the naked eye, however, a well cut stone with good proportions will still release the brilliance and fire of a lower colored diamond, dispersing light in such a way so as to create a beautiful stone.
The Impact of Fluorescence
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. 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 rarely an issue when selecting a diamond and is usually not detectable to the eye.
The impact of fluorescence on price depends on its noticeability. Faint fluorescence has very little effect on a diamond of any color, and therefore has no effect on value. For some higher color stones (D-G), strong fluorescence may give the stone a milky white appearance, which greatly lowers value. Fluorescence often adds value to lower color stones, such as I and lower, as it gives the stones a whiter, brighter appearance.
Clarity
Most diamonds have unique clarity characteristics, much like a fingerprint. These distinguishing characteristics can be classified as inclusions and blemishes. Inclusions are enclosed within a diamond, or they extend into the diamond from its surface. Blemishes are confined to the diamond's surface. These characteristics can detract from the pure beauty of the diamond. When light enters a diamond, it is reflected and refracted out. If there is anything disrupting the flow of light in the diamond, such as an inclusion, a proportion of the light reflected may be lost.
The table below provides an explanation of the clarity grades and demonstrates the effect that clarity has on diamond pricing, assuming carat, cut and color remain the same. To get the most value, we suggest selecting a diamond that is "eye clean" where no internal flaws are visible to the unaided eye. The sample images shown depict how a flaw (inclusion or blemish) may appear under 10X magnification.
Carat
Diamond weight is measured in carats, a small unit of measurement equal to 200 milligrams. Each carat is divided into 100 points. Therefore, a half-carat stone may be referred to as a "50-pointer" or "50-points". Carat weight is the easiest of the 4 C's for gemologists to determine because of the use of sophisticated measuring equipment.
Two diamonds of equal carat weight might vary greatly in value depending upon their cut, color and clarity. This is important because when mounted, one diamond may appear larger than the other, although they actually weigh the same. Because large diamonds are rare, they generally have a greater value per carat. For example, the price of a two-carat stone will be several times higher than four 50-pointers of equal quality.
Determining the Carat Weight that's Right for Her