What is the process for choosing the right lab-grown diamond for a specific design?

Choosing the right lab-grown diamond for a specific design involves working from the setting and overall proportions first, then selecting the diamond’s shape, cut quality, colour, clarity and size. The diamond must suit the design visually and technically, with its grading report, dimensions and durability considered alongside your preferences and budget.

At the consultation stage, we begin by understanding the design itself. An existing setting, a bespoke drawing or a reference style can all provide useful starting points. The intended look will influence the most suitable diamond. A clean, contemporary design may suit a simple round or square outline, while a more distinctive piece could work better with an oval, pear, emerald, marquise or cushion shape. The choice is not only aesthetic: every shape has different proportions, facet arrangements and setting requirements.

For a bespoke ring, we also consider how the diamond will be worn. An engagement ring intended for everyday use may need a setting that protects vulnerable points and edges. A design with exposed corners, such as a princess or pear-shaped diamond, may require carefully positioned claws or protective metalwork. A diamond with a pointed end, including a pear or marquise shape, should not be selected without checking how that end will be secured.

• Define the design and setting: Establish whether the diamond will be the centre stone, a side stone or part of a larger arrangement, and confirm the available space within the mount.
• Choose the shape: Select the outline that suits the design, the wearer’s style and the proportions of the finger or jewellery piece.
• Assess cut quality: Look for effective light return, balanced proportions, good symmetry and a finish appropriate to the chosen shape.
• Select colour: Decide whether the design calls for a bright, colourless appearance or whether a slightly warmer tone is acceptable, particularly when using yellow or rose gold.
• Review clarity: Consider whether inclusions are visible to the unaided eye and whether their position could affect appearance or durability.
• Confirm size and proportions: Compare measurements and face-up appearance rather than relying on carat weight alone.
• Check documentation: Review the independent grading report and ensure that the stone supplied matches its report and inscription where applicable.
• Inspect setting compatibility: Confirm that the diamond’s depth, outline, girdle and culet will work with the proposed mount.

Shape and cut are separate considerations. Shape describes the diamond’s outline, whereas cut describes how it has been proportioned, faceted and finished. A diamond can have the preferred shape but still show weak brightness, uneven symmetry or excessive darkness if its cut is not carefully assessed. For round diamonds, recognised cut information can provide a useful starting point. For fancy shapes, visual examination and comparison are particularly important because grading terminology and appearance can vary more between stones.

When assessing the cut, we look for balanced reflections, lively movement and a face-up appearance that suits the design. Some elongated shapes can show a dark area through the centre, sometimes described as a bow-tie effect. This is not automatically a fault, but it should be viewed in person or through reliable imaging so that its strength is acceptable to you. The same principle applies to areas of darkness, haziness or uneven brightness in any shape.

Colour should be selected with the metal and surrounding stones in mind. A white-metal setting usually places more emphasis on a bright, neutral appearance. Yellow or rose gold can complement a warmer-looking centre diamond, although the setting style and personal preference remain decisive. If a halo or pavé design is included, the centre stone should be considered alongside the smaller diamonds so that the overall piece appears balanced rather than mismatched.

Clarity should be judged by visibility, position and effect. The highest clarity grade is not always necessary for a beautiful design if a lower-graded diamond appears clean to the unaided eye. However, inclusions close to the edge, near a pointed corner or in a structurally important area deserve closer attention. We assess the stone under suitable magnification and in normal viewing conditions, explaining what is visible rather than relying on the grade alone.

Carat weight does not determine the diamond’s visible size on its own. Two diamonds with the same weight can have different face-up measurements because of their depth and proportions. A well-proportioned stone may look larger and brighter than a heavier stone that carries too much weight below the girdle. For a specific design, we compare the diamond’s length, width and depth with the planned setting, the finger coverage required and the proportions of any side stones.

The setting also affects the practical choice. A claw setting allows more light around the diamond and displays more of its outline, but it must be designed to protect corners and points. A bezel setting can provide additional protection and a modern, secure appearance, although it may cover more of the diamond’s edge. Channel and pavé settings require close attention to the consistency of the smaller stones and the strength of the surrounding metal. These decisions should be made before the centre diamond is finalised, as changing the setting can alter the required measurements.

Every selected stone should be checked against an independent gemological grading report. The report should identify the diamond as laboratory-grown, record its shape and measurements, and state the assessed colour, clarity and cut information where applicable. We also verify that the physical diamond corresponds with its documentation. A report supports informed selection, but it does not replace viewing the stone, especially when comparing fancy shapes or assessing the overall appearance of a bespoke piece.

During the selection process, we normally compare a small number of suitable diamonds rather than choosing solely from a specification. This makes it easier to see how differences in cut, colour, clarity and proportions affect the finished design. Where possible, the stones can be considered alongside a design drawing, sample setting or digital representation. The aim is to identify the best balance between appearance, durability, available space and budget.

For a bespoke commission, the final checks include confirming the diamond’s exact measurements, the orientation of its shape, the position of any inclusions, the planned claw or bezel placement and the relationship with any wedding ring or adjoining jewellery. We also consider future maintenance, including whether the setting will allow the stone to be inspected and cleaned properly. Once the diamond and design are approved, the specifications are recorded before the piece is made.

The most suitable lab-grown diamond is therefore not simply the largest or highest-graded option. It is the stone whose shape, proportions, appearance and documented characteristics work together with the design and intended use. A consultation with Steven Charles Quance allows these factors to be assessed together, so that the finished jewellery is appropriately designed, secure to wear and visually consistent with your requirements.