Diamond Guide

A grading report is a starting point. The final decision should combine verified specifications with how the stone actually looks in motion and under useful lighting.

What “lab-grown” means

Lab-grown diamonds have the same carbon crystal structure as mined diamonds. Their growth origin is different. Treatments, growth method and report details should be reviewed when disclosed.

Start with shape

Round brilliants are evaluated heavily on cut and light return. Oval, pear, emerald, radiant, cushion and other fancy shapes require more visual review because outline, bow-tie, windowing, facet pattern and length-to-width ratio can vary even when the report grades are similar.

The 4Cs—in practical order

Cut

Look beyond a single cut label. Review proportions, symmetry, polish, facet alignment and the balance of brightness, fire and contrast. Watch for light leakage, persistent dark or “dead” areas and an uneven pattern as the stone moves.

Colour

Compare the body colour face-up and from the side under neutral lighting. In near-colourless stones, a visible brown or grey tint can matter more than a one-grade difference on paper.

Clarity

Check the type, size and position of inclusions—not only the grade. Confirm whether they affect transparency, durability or appearance. A stone can look milky or hazy even when individual inclusions seem small.

Carat

Carat is weight, not visible size. Compare the millimetre measurements and proportions because two stones of the same carat weight can face up differently.

Checks beyond the 4Cs

Transparency: reject unexplained milkiness, haze or reduced crispness.
Undertone: inspect for unwanted brown, grey or other tint.
Fluorescence: review the report and, when relevant, appearance under UV and daylight.
Pattern: look for balanced facets, a pleasing bow-tie in elongated shapes and no distracting dead zones.
Light performance: use movement and more than one lighting condition to assess brightness, leakage and contrast.
Report match: match the report number and measurements to the stone when a report is listed.

Ring-size guide

Use a ring that fits the intended finger and measure its inside diameter in millimetres, or have the finger measured by a jeweller. Measure at the time of day the ring will usually be worn. Wide bands may need a different fit. Send the measurement method, country sizing system and preferred fit; QIORA will confirm the size used for the item in writing.