A nick is a small surface blemish found on a diamond, typically appearing as a tiny break or indentation along the girdle or facet junctions. It is too small to be classified as a chip, but it can still impact the diamond’s polish grade and overall appearance. Nicks often occur due to accidental impact, improper handling, or wear over time.
Characteristics of a Nick
Size: Small, shallow indentation (smaller than a chip)
Location: Most commonly found on the girdle, but can also occur on facet edges
Appearance: Can look like a tiny white mark, scratch, or indentation under magnification
Cause: Often results from mechanical wear, accidental bumps, or improper handling during cutting, setting, or daily wear
Impact of a Nick on a Diamond’s Quality
1. Polish Grade
A nick affects the polish grade of a diamond, as it disrupts the smoothness of the surface.
If minor, it may not significantly lower the diamond’s overall grade, but if noticeable, it can result in a lower polish rating on a grading report from DCLA, GIA, or AGS.
2. Visibility & Aesthetic Impact
Small nicks on the girdle: Often invisible to the naked eye and do not affect brilliance.
Larger nicks on facet edges: Can slightly affect light performance, especially if they disrupt the diamond’s symmetry.
3. Durability & Wear Resistance
A single, shallow nick usually does not impact a diamond’s structural integrity.
However, multiple or deep nicks along the girdle may make the diamond more susceptible to chipping over time, especially if the girdle is very thin.
Nick vs. Other Diamond Blemishes
Blemish Type Description Impact on Diamond
Nick Small, shallow indentation on the girdle or facet edge Minor, affects polish but not durability
Chip Larger, more visible break in the diamond, often near the girdle or culet Can weaken durability and lower value
Scratch A fine line on the diamond’s surface Affects polish but can often be removed
Abrasion Small, worn-down facet edges from prolonged wear Reduces brilliance and can make the diamond look dull
Can a Nick Be Repaired?
Polishing/Recutting: A minor nick can sometimes be polished out by a professional jeweler. However, this may slightly reduce the diamond’s carat weight.
Re-setting: If the nick is on the girdle and affects durability, the diamond can be set in a way that protects the weak spot (e.g., a bezel setting).