Polish Poor (Pol P)
Polish Poor (Pol P)
The lowest GIA polish grade, indicating prominent surface defects that reduce brilliance
Polish Poor, abbreviated Pol P on a GIA diamond grading report, is the lowest of the five polish grades GIA assigns. A stone graded Pol P shows prominent polish marks, scratches, or surface irregularities visible at 10× magnification, with defects severe enough to noticeably reduce brilliance and overall light return even to careful unaided observation in some cases.
What it indicates
Polish Poor stones typically display heavy polish lines across multiple facets, severe abrasions on facet junctions, prominent burn marks or surface graining, or scratches deep enough to be visible without magnification. The defects are often the result of damage during wear or mounting rather than an original cutting problem, although stones cut by inexperienced or rushed operators can also fall to this grade as cut.
Pol P is genuinely rare on modern grading reports. Established cutting centres do not produce stones at this level under normal conditions; the grade more often appears on older stones that have suffered wear, on stones that have been damaged in a setting and not yet repolished, or on amateur work submitted for laboratory grading.
Effect on appearance
Unlike the differences between higher polish grades, the difference between Pol P and the grades above is often visible to the unaided eye. The stone appears slightly cloudy or muted, the facet edges look indistinct, and the brilliance characteristic of a well-cut diamond is reduced to the point of being apparent in side-by-side comparison. Light return is reduced because surface irregularities scatter incident light away from the geometric paths the cutter intended.
Market consequences and remediation
Pol P stones command a substantial discount in the polished-diamond market and are generally not accepted in mainstream retail or investment-grade channels. The standard remediation is professional repolishing, which can usually bring a Pol P stone up several grades to Pol G or Pol VG. Repolishing removes a small amount of weight and may slightly alter proportions, but for stones of meaningful size the price improvement easily justifies the work. The decision to repolish or accept the discount is one a competent cutter or appraiser should make rather than a generalist.
For stones below approximately half a carat, the economics of repolishing rarely make sense, and the stone is more likely to be sold at the discounted Pol P price into the budget commercial market or used in applications where polish quality is not material to value.