The Four C’s of Diamonds

Before you start diamond shopping, you want to have an understanding of what you’re buying. This guide simplifies the four C’s of diamonds: cut, color, clarity and carat weight, so you can select your diamond based on the same criteria jewelers use to grade them.


Diamonds Cohasset Mass

A diamonds cut is an essential component of its brilliance in terms of how it reflects natural light or its sparkle. All 4C’s, when close to perfection, make a diamond stand out in any arrangement. But even with color, clarity & carat close to perfect and a cut being fair or poor, a diamond will seem pale or dull to the eye. The better a diamond is cut, the more brilliant it will be.

The well-cut diamond is faceted with the angle placed to best allow the light to reflect within the diamond and then return to the eye of the beholder. Diamonds may be cut and polished in various shapes to enhance their beauty. Diamonds reflect light from one facet to another, and then disperses it through the top of the stone. If the cut of a diamond is too deep, some of the
light escapes through the opposite side of the pavilion. If the cut is too shallow, light escapes through the pavilion before it can be reflected.


The less color a diamond carries the more sought after it becomes. Color to a diamond is likened to that of sunlight to the sky. The less color a diamond possesses the less impedance it has to its brilliance. Colorless diamonds allow light to be untainted and reflects light and brilliance to its highest potential. While we may think of diamonds as being colorless, they can have hints of yellow or brown.

Truly colorless diamonds, ranked D – F on the diamond quality pyramid, comprise the highest grade of color.

Near colorless, or white diamonds are ranked G – J.

Diamonds labeled K and L are also called top silver: M and N are known as faint yellow: O, P and Q are very very light yellow or top brown in color.


A flawless diamond is said to have zero or almost impossible to see inclusions within its physical composition. Clarity is graded on the number of inclusions, frequency, size and locations. The fewer in number these imperfections are, the greater the value of the diamond and the “cleaner” a diamond appears to the eye or loop.
Almost all diamonds have natural characteristics, or inclusions unique to the particular stone. Some are obvious at a glance, some are undetectable with the naked eye. Inclusions affect a diamonds ability to refract light, thus determining the overall brilliance. The fewer the inclusions, the more valuable the stone. Flawless diamonds are
rare, and are usually found in crowned collections. Diamonds with very, very small (VVS) or very small (VS) inclusions are highly valued and are closer to the top of the diamonds scale. Diamonds graded I1-I3 has inclusions that can be seen by the untrained eye.


The scale of diamonds weight is measured in carats. The higher the carat (size) of a diamond the more valuable and rare it becomes. Cohasset Jewelers carries diamonds of all carat sizes so as to offer our customers the convenience of a wide selection while providing the best possible cost.

The carat weight represents the easiest of a diamond’s assets to measure. Its size “a” carat is about 0.2 grams and a carat is also equal to 100 points. This is done so that diamonds of less than a carat can be accurately measured. For example, a 50 point diamond (written as 0.50) is the same as a one-half carat diamond.