Diamond Table
April 12, 2023
Everything You Need to Know About a Diamond’s Table
A diamond’s depth and table can have a major impact on a gem’s overall appearance and value. Both are measured and listed on the GIA specifications report, but these two characteristics can affect how “eye-clean” a diamond appears. There is not necessarily a “best” depth or table measurement for different diamonds because it is dependent on the cut you may be considering. For example, the ratios that work great for a cushion cut might be unfavorable for a round diamond.
What is a Diamond Table?
A diamond’s table refers to the flat, table-like facet on its surface- typically the largest flat surface facet when you look straight down on a diamond. Because it is the largest facet on a diamond, it can have a lot of impact on how brilliant and sparkly the diamond appears. As the largest top facet, the table lets light into the diamond and refracts it among other facets, giving the diamond its unique, sparkly appearance.
You’ll notice that a diamond’s table is the largest facet and it should be able to let light in. A bigger table isn’t necessarily better. For each diamond shape, there needs to be balance- large enough to let light in, but constrained enough so that light doesn’t affect the crown of the diamond.
The average table size is commonly expressed as a percentage of the diamond’s average girdle diameter. Table percentage is calculated by measuring the width of the table as a percentage of the total width of the diamond. The wider the table is relative to the diamond’s total width, the larger the diamond’s table percentage.
Similar to other aspects of a diamond’s quality, the table of a diamond is graded from poor to excellent. An excellent quality table percentage allows the optimal amount of light into a diamond, creating a beautiful sparkle. A diamond with a poor table appears dull.
| Diamond Shape | Excellent/Ideal Cut | Good Cut |
|---|---|---|
| Round | 54%- 57% | 52%-53% |
| Princess | 69%- 75% | 56%-67% |
| Cushion | 61%-68% | 58%- 60% |
| Asscher/Emerald | 60%- 68% | |
| Oval | 53%- 63% | |
| Pear | 53%-65% | |
| Radiant | 61%-69% | |
| Heart | 56%- 62% | |
| Marquise | 53%- 63% | 52%- 64% |