Are diamonds still an executor’s best friend? The impact of lab grown diamonds on estate administrations…

With their recent popularity, lab diamonds have flooded the market with consumers preferring to opt for a more conflict-free and ethically produced stone. As the name suggests, lab diamonds are produced in a laboratory setting and are chemically and physically identical to natural diamonds.

As the popular option, they have saturated the market, pushing prices down and resulting in lab diamonds being even more affordable than before; particularly given recent 2025 statistics showing an even further fall in diamond prices.

Whilst natural diamonds take billions of years to form, a lab diamond can be grown and produced in as little as 1-2 weeks. However, the short production time means that lab diamonds are less likely to hold their value compared to natural diamonds, with re-sales generating around 30-40% less than the initial purchase price.

So where natural and lab diamonds look identical to the naked eye, how can executors be sure that their inheritance tax valuation and the sale price is truly reflective of the diamond’s actual value, particularly when that sparkle looks the same?

What can you do to protect that million-dollar sparkle?

With duties to realise estate assets at maximum value, executors will need to consider whether any diamonds and jewellery should be sent for specialist testing to establish if they are lab or natural diamonds prior to any valuation. The testing fees can start upwards from £200 per diamond and a GIA certification report (the formal diamond grading document confirming the colour, clarity, cut and carat) can be produced to give executors the peace of mind and confidence in selling later, as well as providing subsequent buyers with the assurance needed for their purchase.

With the burden of high testing fees, you can assist your executors with some simple action now:

• 1. Keep the original grading certification documents (IGI /GIA /HRD / EGL), GIA number or QR code in a safe place with a picture of the associated item for easy identification;
• 2. Keep any jewellery valuations in a safe place; and
• 3. Update your confidential Will letter of wishes with details and guidance to your executors and ensure the right people are appointed as executors.

Not only will the above steps assist your executors and lower estate administration costs, it will also ensure that your beneficiaries inherit the maximum value possible from your estate.

So, this Valentine’s Day, be sure to keep the proper documentation and let’s ensure that diamonds remain an executor’s best friend.

If you would like to review your Will or have any questions, please contact one of our Succession & Tax solicitors.