How to Tell if a Diamond Is Genuine

A diamond’s beauty is immediate, but confirming exactly what it is requires more than a quick glance. If you are considering a diamond ring, pendant, bracelet or inherited piece, the safest approach is to rely on professional assessment rather than internet “tests”.

A qualified jeweller can assess the stone, its setting and any supporting documentation without putting the jewellery at risk.

What does “genuine diamond” mean?

A diamond is made of crystallised carbon. Both natural diamonds and laboratory-grown diamonds are real diamonds: they have the same fundamental material composition, although their origins are different.

Diamond simulants, such as cubic zirconia and moissanite, may look similar but are different materials altogether. A professional can identify the difference using suitable equipment and expertise.

If you are buying a diamond, it is helpful to ask clear questions:

• Is the diamond natural or laboratory-grown?

• Is a grading report or certificate available?

• What are the diamond’s cut, colour, clarity and carat weight?

• Has the stone been treated or altered in any way?

Check for a grading report

For important diamond purchases, a reputable grading report is one of the most useful pieces of information you can have. It records the characteristics of a specific diamond and may include a report number or laser inscription reference.

A report can provide details about the 4Cs:

• Cut: How effectively the diamond has been fashioned to return light.

• Colour: The degree to which a white diamond appears colourless.

• Clarity: The internal characteristics and surface features present.

• Carat weight: The diamond’s weight, not its visible size alone.

A report is valuable, but it should be considered alongside an expert inspection of the actual stone and jewellery.

Look at the setting and craftsmanship

The setting can reveal a great deal about the piece. Quality diamond jewellery is carefully constructed so that the stone is secure and its setting is appropriate for the design.

A jeweller may examine:

• The condition and shape of the claws or bezel around the stone

• Whether the stone is secure

• The quality of the metalwork and any hallmarks

• The consistency of the stones in multi-diamond jewellery

• Signs of wear, repair or replacement

This is particularly important for pre-owned jewellery. A beautiful vintage ring may have a history of resizing, restoration or stone replacement that is worth understanding before purchase.

Avoid at-home diamond tests

Many online diamond “tests” are unreliable. Some can also scratch, loosen or otherwise damage a stone or its setting.

Avoid:

• Scratching a stone against glass or another surface

• Heating or freezing jewellery

• Tapping, scraping or striking the setting

• Assuming that sparkle alone proves a stone is a diamond

• Relying on a loupe without experience

A diamond’s sparkle depends on many factors, including its cut, lighting, cleanliness and setting. Visual inspection alone is not enough to confirm identity or value.

Why professional assessment matters

A jeweller can use specialised tools to distinguish between diamond, simulants and other gemstones. They can also advise on the diamond’s condition, setting security and whether a valuation or further laboratory assessment is appropriate.

At Miller Gold & Co, we assess the condition, gemstones, settings, metal and craftsmanship of every piece we select. This allows you to choose pre-owned diamond jewellery with greater confidence and a clearer understanding of what makes each piece special.

Buying a diamond with confidence

The best diamond is not simply the largest or brightest-looking stone. It is the one that suits your taste, budget and intended wear, with information you understand and a condition you can trust.

Explore Miller Gold & Co’s diamond jewellery collection, or contact us for guidance on a particular piece.

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