130 East 10th Street                   (765) 642-7978      Toll Free: (877) 6-ALLANS
Anderson, IN  46016

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The Four C's

Allan's Jewelry - Your source for diamonds.

The Four Characteristics that determine the quality of a diamond.

Two diamonds may, at first glance, look alike, but the truth is that they are very different. Although they may be of equal size, each dia­mond has char­ac­ter­is­tics unique to itself, so they may have unique values.

To understand these differences is to understand the 4C’s. Cut, Color, Clarity and Carat Weight. It is the combination of these four characteristics that determines the value of a dia­mond. Let our diamond experts explain the 4 C’s to you in more detail when you visit our store.


Many people confuse cut with the shape of a diamond. The shape you select is a matter of individual taste, and today your choice is only lim­ited by the skill and imagination of the crafts­man. It is their effort dur­ing every stage of the fash­ion­ing process that reflects the max­i­mum amount of light back to the eye. Most round, brilliant-cut or fancy-?shaped diamonds possess 58 care­fully angled flat surfaces, called facets, whose placement will affect the fire, brilliance and ulti­mate beauty of your diamond.

How a Diamond handles light

  • 1. When a diamond is cut to good proportions, light is reflected from one facet to another and then dispersed through the crown, or the top of the stone.
  • 2. If the cut of the diamond is too deep, some light escapes through the oppo­site side of the pavilion, or bottom.
  • 3. If the cut is too shallow, light escapes through the pavil­ion before it can be reflected.

The different facets of a round, brilliant-cut diamond


The seven most popular shapes of a diamond.

Brilliant Marquise Pear Emerald Oval Heart Square
Brilliant Marquise Pear Emerald Oval Heart Square


The most prized dia­monds are col­or­less dia­monds, because their beauty depends entirely upon their remark­able opti­cal prop­er­ties. In such dia­monds, all the col­ors of the rain­bow are reflected back to your eye. While the major­ity of gem dia­monds appear to be col­or­less, oth­ers can con­tain increas­ing shades of yel­low to brown, some of which are referred to as cham­pagne dia­monds. Other dia­monds of excep­tional color – red, blue, green, pink, and amber – are knows as “Fancies.”

The color grad­ing scale varies from totally col­or­less to light color or tinted. The dif­fer­ence between one grade and its neigh­bor is very sub­tle. Experts never try to remem­ber color; they use mas­ter dia­monds of know color for comparison.

ColorlessNear ColorlessFaint YellowVery Light YellowLight Yellow


Because of their unique optical properties, diamonds, more than any other gemstone, are capable of producing the maximum amount of brilliance. While minute crystals of dia­mond or other minerals are con­tained in almost all diamonds, a dia­mond that is virtually free of inclusions and surface markings will be judged as flawless. In these diamonds, nothing interferes with the passage of light or spoils the beauty. But these diamonds are extremely rare and will com­mand a high price.

To determine a diamond’s clarity grading, it must be exam­ined under a 10x magnification by a trained, skilled eye. What minute inclu­sions there may be make every dia­mond unique. These are, in fact, nature’s fin­ger­prints and do not mar the diamond’s beauty nor endan­ger its durability. With­out high mag­ni­fi­ca­tion, you may never see these inclu­sions. However, the fewer there are, the rarer your diamond will be.

fl if vvs vs si iii
Flawless Internally Flawless
minor surface blemishes
Very Very
Small Inclusions
Very Small
Small Inclusions Inclusions: Visible
to the naked eye

Carat Weight And Total Carat Weight

With all precious stones, the weight and therefore the size, of a diamond is expressed in carats. That is abbreviated as CT or CTTW.

One carat is divided into 100 “point” so that a dia­mond of 25 points is described as a quarter of a carat or 0.25 carats. Size is the most obvious factor in determining the value of a diamond, but now you know that two equal sizes can have very unequal prices depend­ing on their qual­ity. How­ever, remem­ber that dia­mond of high qual­ity can be found in all size ranges. Here are some other examples that show that approximate size of diamonds of varying carat weights.

Quarter Carat Half Carat One Carat One And One Quarter Carat One And One Half Carat One And One Quarter Carat Two Carat Two And One Half Carat Three Carat
0.25 CT 0.50 CT 1.00 CT 1.25 CT 1.50 CT 1.75 CT 2.00 CT 2.50 CT 3.00 CT