How to Choose a Beautiful Lab-Grown Diamond

A grading report can tell you a great deal about a lab-grown diamond, but it cannot tell you exactly how that diamond will look on your hand. Two stones with similar carat, color, clarity, and even cut grades can still have very different personalities. One may look bright and lively across the entire face; another may appear dark, sleepy, or smaller than expected.

The goal is not to buy the most impressive collection of grades. It is to choose a diamond whose beauty, size, and price work together for you.

Start with the certificate—but do not stop there

A reputable grading report confirms the diamond’s identity and records important quality characteristics. Use it to verify carat weight, measurements, color, clarity, polish, symmetry, fluorescence, and growth information. It is an essential screening tool.

What the report cannot fully capture is the way the facets work together as the diamond, light, and viewer move. That is why imagery and expert review matter. The certificate narrows the field; the diamond itself makes the final argument.

Give cut quality priority

Cut determines how effectively a diamond gathers and returns light. A well-cut diamond can look bright from edge to edge, create balanced contrast, and produce crisp flashes as it moves. A poorly coordinated cut may leak light or hold large areas of darkness even when the color and clarity grades look impressive.

For round brilliants, an overall cut grade provides a useful starting point, but the top grade still contains a range of proportions and appearances. For fancy shapes—such as oval, pear, marquise, radiant, cushion, emerald, and Asscher—the grading report may not provide an overall cut grade at all. Measurements, facet pattern, outline, symmetry, and video become even more important.

Why “Excellent” Is Only the Starting Point

These two real diamonds demonstrate why the grading report is the beginning of the evaluation—not the end. A broad top-grade category can include very different levels of optical symmetry and face-up patterning.

Both stones may carry an excellent cut grade, but their face-up patterns tell a different story. The Osiris Ideal™ selection displays cleaner arrows, stronger optical symmetry, and more organized contrast. This is why I evaluate the diamond itself—not simply the grade printed on its report.

Judge the face-up size, not carat weight alone

Carat measures weight, not visible spread. Two diamonds of the same carat weight can have noticeably different length, width, and face-up presence. A stone that carries too much weight in its depth may look smaller from the top. A very shallow stone may spread well but sacrifice light performance or durability.

Compare the millimeter measurements and consider the shape’s length-to-width ratio. The right ratio is partly personal: some buyers prefer a softly rounded oval, while others want a longer, more elongated silhouette. The same is true of cushions, radiants, pears, and marquises.

Know what to watch for in each shape

• Round: Look for even brightness, balanced contrast, and a crisp, symmetrical pattern.
• Oval, pear, and marquise: Some bow-tie contrast is normal, but a heavy, dark band that stays fixed across the center can distract from the stone.
• Radiant and cushion: Faceting styles vary widely. Decide whether you prefer a crushed-ice look, larger defined flashes, or a balance of both.
• Emerald and Asscher: Step cuts reveal clarity more readily. Look for clean, deliberate bands of light and an appealing hall-of-mirrors effect.
• Princess: Check for a lively center, balanced outline, and protected corners in the final setting.

Use color and clarity where they matter

Higher grades are not automatically more beautiful. The best value often comes from choosing a diamond that looks colorless enough and eye-clean enough for its shape, size, and setting. Step cuts generally reveal inclusions more easily than brilliant cuts. Elongated shapes may concentrate color near the tips. Yellow or rose gold can also change how sensitive you are to body color.

An eye-clean diamond can contain inclusions that are visible under magnification but not noticeable in normal wear. What matters is the inclusion’s type, size, color, relief, and location—not only the clarity grade printed on the report.

Review the actual imagery carefully

A 360-degree video is most useful when you know what it can and cannot show. Look for even light return, distracting dark areas, asymmetry, transparency issues, obvious inclusions, and whether the outline feels balanced. Remember that lighting setups differ between suppliers, so do not compare brightness from unrelated videos as if the photography were identical.

If a diamond interests you, save its certificate number and ask for a second look before purchasing. I can review the proportions, report, available video, and how the stone fits the setting you have in mind.

Match the diamond to the ring

A beautiful loose diamond still needs to work with the setting. The head must be built for its actual dimensions—not simply its carat weight. Consider how high the diamond will sit, whether a wedding band should fit flush, how the prongs interact with the shape, and whether the ring’s side stones or halo are proportioned correctly.

This is especially important for custom and semi-custom engagement rings. Selecting the center diamond and setting as one design decision produces a more cohesive result than treating them as unrelated purchases.

A practical lab-grown diamond checklist

• Confirm the grading report and inscription.
• Compare length, width, depth, and face-up spread.
• Review cut proportions and facet pattern.
• Check for distracting darkness, bow tie, or windowing.
• Evaluate inclusions for visibility and location.
• Consider the setting, metal color, and desired profile.
• Ask for an expert review before making the final choice.

Choose with more confidence

You can search certified lab-grown diamonds across our global network, or begin with the smaller group of personally reviewed stones inside The Osiris Diamond Vault. When a diamond catches your eye, send it to Osiris for a personal review before you commit.