Stone Authenticity
A note from Catherine on how every stone in this house is verified — and why two independent tests, from two different sources, are the floor, not the ceiling.
Every stone is tested twice, by two independent parties, before it is set.
The first evaluation happens at my bench. I examine every stone personally — identity, treatment disclosure, visible characteristics — before it goes anywhere. The second evaluation happens at Stuller's bench in Lafayette, Louisiana, when the stone arrives for setting. Their protocol covers the same ground: identification, synthetic screening, treatment verification, comparison against the documentation the stone arrived under.
Neither evaluation is a formality. Neither party has seen the other's work when they do theirs. If a stone I sourced arrives at Stuller's bench and their findings don't match my documentation, it gets flagged before it gets set. That's the system working.
What the testing covers.
For diamonds, each stone is individually screened for synthetic detection and undisclosed treatments. A stone sold as natural is tested to confirm it isn't lab-grown. A stone sold as lab-grown is tested to confirm it isn't simulant. Treatments — HPHT color enhancement, fracture filling, laser drilling for clarity — are identified and disclosed before the stone reaches a customer.
For colored stones, each gem is identified against its stated variety and matched to the sourcing documentation it arrived under. Treatments common to the variety — heat treatment in sapphires and rubies, oiling in emeralds, irradiation in certain blue topazes — are noted and disclosed. If a stone presents characteristics inconsistent with its documentation, it doesn't ship.
The testing protocol is the same whether the stone is a $200 accent or a $5,000 center stone. Size and price don't change the standard.
What it means for you.
When you receive a Catherine Peck piece, the stone it contains has been evaluated by me at my bench and by Stuller's team at theirs. Two independent assessments, neither of which knew the other's outcome at the time. If those assessments disagreed at any point, the stone wouldn't have made it into the piece.
This isn't a certification. Certifications are third-party documents produced for specific stones, usually above a certain size threshold, at the buyer's request or the seller's discretion. The double-verification protocol described here applies to every stone in this house, certified or not — it's the baseline, not a premium service.
Most fine jewelry houses do not describe their stone-verification process in public. I'm describing ours because it's the right thing to put on the page, and because you're spending real money on something you're going to wear for the rest of your life. You should know what you're buying.
— Catherine