Poe HITU Pearl Grading Standards

At Poe HITU, every Tahitian pearl is assessed individually according to the traditional Tahitian A–D grading system. Our objective is to provide a clear, consistent and transparent indication of quality while respecting the natural individuality of each pearl.

A pearl’s quality grade is determined primarily by two characteristics:

• Surface quality: the proportion of the pearl’s surface that is free from visible imperfections.

• Luster: the intensity, sharpness and depth of the light reflected by the pearl.

Size, shape, body colour and overtone are recorded separately. These characteristics do not determine the technical quality grade, but they can significantly influence a pearl’s rarity, desirability and market value.

Tahitian A–D grading system

Surface characteristics

Tahitian pearls are organic gems formed within a living oyster. Small pits, growth lines, rings and other surface characteristics are therefore natural features rather than manufacturing defects.

During grading, we consider:

• The percentage of the surface affected

• The number and depth of the imperfections

• Their visibility and position

• Whether they can be concealed by a jewellery setting

• Their effect on the pearl’s overall appearance

A pearl with minor characteristics concentrated on one side may still be highly suitable for jewellery when its cleanest and most attractive face can be presented.

Luster

Luster is one of the most important indicators of pearl quality. It describes both the brightness of the surface and the depth and sharpness of the reflected light.

A pearl with exceptional luster displays crisp reflections and a luminous appearance that seems to originate from within the pearl. Lower-luster pearls have softer, less defined reflections and may appear comparatively dull.

At Poe HITU, strong luster is essential when selecting pearls for our finest grades.

Colour, overtone and rarity

Tahitian pearls occur naturally in a remarkable range of colours. Their body colour may be enhanced by overtones such as green, blue, aubergine, bronze, silver, gold or cherry.

Colour is evaluated separately from technical quality. Nevertheless, a rare and particularly vivid colour combination can substantially increase a pearl’s desirability and value. For example, an intense cherry or peacock overtone may command a premium over a more common silver-grey pearl of the same technical grade.

Shape and size

Shape and size are also assessed independently from surface quality and luster.

Round pearls are traditionally the rarest, but drop-shaped, oval, button, circled and baroque pearls can be equally desirable when they possess harmonious proportions, excellent luster or distinctive natural character.

Larger pearls are generally rarer, although size alone does not indicate superior quality. A smaller pearl with exceptional luster and a clean surface may be considerably finer than a larger pearl with weaker visual characteristics.

Our final assessment

Although grading criteria provide a structured framework, no system can fully express the beauty of an individual pearl. Two pearls with the same technical grade may differ significantly in colour, character, rarity and overall visual impact.

For this reason, Poe HITU combines careful technical assessment with an evaluation of the pearl as a complete natural gem. Every grade is intended to provide an honest quality reference, while each pearl’s individual beauty is considered separately.

A note on international grading terminology

Pearl grading is not governed by one universal international standard. The commercial A–AAAA system is used by many pearl dealers, but its interpretation can vary between companies.

The Gemological Institute of America does not assign pearls an A–AAAA grade. Instead, the GIA evaluates pearls using seven value factors: size, shape, colour, luster, surface quality, nacre quality and matching.

Any A–D to A–AAAA comparison should therefore be understood as an approximate commercial reference rather than an official or exact equivalence.