"HOW TO BUY A DIAMOND WITHOUT GETTING RIPPED OFF"
|
|
|
| Home l About Us l Jewelry Catalog l Diamond School l Diamond Book l News & Information l Glossary l Birthstones l Wedding Anniversary Gift List l All about Gold l Facts to Know l Trivia l Pearls l |
Color * Clarity * Cut * Carat * More about Cut >>>
Cut
While nature determines a diamond's color, clarity, and carat weight, the hand of a master craftsman is needed to release its fire and beauty. The cut gives each diamond its unique sparkle and brilliance by allowing the maximum amount of light to enter and reflect back out of the diamond.
If the cut is too deep or too shallow light will spill
through the side or bottom and be lost, resulting in a less brilliant display
and thus, a less valuable diamond. The cut plays a big part in determining the
value of a diamond. A well-cut diamond will be considerably more beautiful and
valuable than a poorly cut stone of the same size, clarity, and color.
| Well proportioned | Too Deep | Too Shallow |
 |
 |
 |
If a diamond seems too cheap for its grade it very often has a poor cut.
Four factors: depth, table size, polish, and symmetry determine the "cut" quality.
The most important are the depth of the diamond and the table size (both are reported as a percentage of the diameter, or width, in a fancy shape). These two measurements determine if the diamond is too shallow, well proportioned, or too deep.
The polish refers to the finish on the diamond, and the symmetry refers to how well aligned the facets are.
The following table shows the ranges of acceptability for each factor in different shaped stones
For round diamonds only:
| Acceptable (well cut) | Unacceptable (poor cut) | |
| Depth | 57-64% | Less than 57% or more than 64% |
| Table | 53-65% | Less than 53% or more than 66% |
| Polish | Cert states good or better | Cert states fair or poor |
| Symmetry | Cert states good or better | Cert states fair or poor |
For fancy shapes we have different specifications. A fancy diamond must have a good shape. Shape is a function of the ratio between length and width. Percentage depth differs for fancies (see table below).
Shape is most important in fancies:
| Shape | Length to Width Ratio | Acceptable Depth (well cut) |
| Emerald Cut | 1.40-1.70 | 60-70% |
| Marquise | 1.75-2.00 | 60-75% |
| Oval | 1.35-1.70 | 58-65% |
| Pear | 1.40-1.70 | 58-65% |
| Princess | Either square or rectangular | 60-75% |
| Radiant | Either square or rectangular | 60-75% |
Note: length divided by width gives above ratio.
