Resetting an heirloom diamond: what to know first

An inherited diamond is often the most valuable thing in a ring, and in every sense that matters. Resetting it well is a matter of care in the right order: understand the stone, then design around it. Here is how I approach it in the studio.

Step one: document the stone

Before anything is removed, I record the diamond as it sits: its shape, approximate measurements, visible characteristics, and the condition of the setting. Once it is out, I measure it precisely. This protects you, and it is the basis of every design decision that follows. If you ever leave a stone with any jeweler, ask how they will document it.

Step two: remove and inspect

Prongs are opened carefully and the stone is lifted out. Out of the setting I can see what was hidden: the girdle (the thin outer edge), the pavilion underneath, and any chips, abrasions, or small fractures. Decades of wear can chip a girdle, especially where a prong pressed against it or where the stone sat high and caught on things.

Most of what I find is minor and can be placed under a prong or bezel in the new design so it is protected and unseen. If there is significant damage, we talk it through before going further.

Old cuts are not flaws

Many heirloom diamonds are old mine or old European cuts, cut by hand before modern proportions became standard. They often have a small table, a tall crown, and a small open facet at the bottom called an open culet. They do not sparkle in the same crisp way a modern round brilliant does; their light is broader and softer, often described as more romantic. I love working with them.

I seldom recommend recutting. A recut can make a stone look more modern, but it removes weight, sometimes a good deal, and replaces the character that made the stone yours. It is worth considering mainly when a stone has damage that affects its safety or appearance, and then only after you understand exactly what would be lost.

Should you have it graded?

You do not need a grading report to reset a diamond. For a significant stone, though, I often suggest one from the Gemological Institute of America, which developed the four Cs grading system. A report documents the stone's identity, measurements, and grades. It is useful for insurance and appraisal, and it confirms whether the diamond is natural. Families are sometimes surprised in either direction, so it is good to know before you invest in a new setting.

Designing the new setting

An older stone needs a setting built to its exact proportions. A tall crown and deep pavilion need a taller head than a shallow modern stone of the same weight. Off-round outlines, common in old mine cuts, need prongs placed precisely to sit flush. These details are why I design around the stone rather than fitting it into a stock mounting.

Choosing for protection

• Bezel:metal surrounds the girdle. The most protective choice and very comfortable. It shows slightly less of the stone's profile.
• Prongs: four or six prongs show the most diamond. Placement matters more than number. A claw prong at each point of a pear or a V-prong at each corner of a princess cut protects the vulnerable tips.
• Half bezel or hybrid: protects two sides while leaving the stone open to light.

I also think about height. A lower setting catches less on sweaters and doorframes, which is kinder to an older stone with a thin girdle.

Metal choice

Platinum is dense and holds stones very securely, which is why many jewelers favor it for prongs. 18k gold is beautiful in yellow and rose and complements the warmth of many older stones. I often combine them, a yellow gold band with platinum prongs for example. If you would like to reuse metal from the original ring, read my guide to reusing old gold first.

Time and cost

Resetting often takes six to ten weeks once the design is approved. Redesigns are quoted individually, and because the stone is already yours the quote centers on the setting and the work. For the broader question of reimagining a family ring, read how to redesign your grandmother's ring, or book a time to bring the stone in.