Diamonds 101: What is Girdle Thickness?


There’s a term you may have heard of when discussing Diamonds. That term is the “girdle” of the diamond, or the perimeter that separates the top of the Diamond (known as the crown) and the bottom (known as the pavilion).

Though the girdle of a Diamond may not affect the Diamond’s appearance, it can throw off the Diamond’s symmetry, making it worth less than it could be. Furthermore, depending on the width of the girdle, the Diamond may or may be less prone to damage.

There are six girdle measurement ratings, ranging from “extremely thin” to “extremely thick.” They are as follows:

  • Extremely Thin: The most delicate girdle; may easily chip
  • Very Thin: Looks great but is still somewhat delicate
  • Thin/Medium: The ideal girdle size.
  • Slightly Thick / Thick: Nearly ideal girdle size
  • Very Thick: Good girdle size
  • Extremely thick: Generally considered too large, as visually it takes away from the size of the Diamond.