Diamond Cut Education - Brilliant Round Diamonds
Nature determines a diamond's color, clarity and carat weight, and cut is the only one of the 4Cs which is influenced by the human hand. Cut refers to the angles and proportions the cutter creates in transforming a rough diamond into a polished diamond. Diamond cutting is based on scientific formulas and requires a lot of skill and training. When light enters a well-cut diamond, it will reflect from one mirrow-like facet to another, disperse and reflect back through the top of the stone. This gives the diamond its brilliance and fire.
 |
 |
 |
| ideal cut | excellent cut | very good cut |
 |
 |
 |
| good cut | fair cut | poor cut |
Diamonds that are cut too deep lose light through its side; they also have a relatively smaller table and diameter, so look relatively smaller. Diamonds that are cut too shallow leak light through the bottom, and result in less brilliance.
 |
 |
 |
| deep cut | ideal cut | shallow cut |
Before cutting a rough diamond, the cutter usually needs to decide whether to maximize its carat weight or to make it a better-cut stone to have extra brilliance and sparkle. To make an ideal cut diamond, the cutter will often need to cut away more than 50% of the rough diamond, so the diamond's proportions fall under certain precise proportion range. The most important proportion people look at a diamondis its depth to diameter ratio, and its diameter of the table to the diameter of the diamon ratio. When the cutter polishes tiny surfaces onto the rough diamond, he creates the crown, culet, table, girdle and pavilion of the diamond.
Diameter: The width of the diamond as measured through the girdle.
Table: The largest facet of a diamond, located at the top of the diamond facing out from the setting.
Crown: The top portion of a diamond above the girdle and surrounding the table.
Girdle: The intersection of the crown and pavilion which defines the perimeter of the diamond.
Pavilion: The bottom faceted portion of a diamond, extending from the girdle to the culet.
Culet: The facet at the tip bottom of a diamond. People prefer culet graded as "none" or "small", which is not visible with the naked eye. If the culet is medium to large, when the diamond is viewed from the table, it will look like there is a hole in the bottom of the stone.
Depth: The height of a gemstone measured from the culet to the table. Read more education about diamond depth & table.