The three C's nobody mentions
The four C's describe the stone. These three describe the transaction, and they are the ones that determine whether you got a fair deal.
Certification
A diamond report from an independent laboratory is not a formality. It is the only thing standing between you and someone else's opinion of what you are buying. Reputable labs grade to consistent, published standards; less reputable ones are known throughout the trade for grading generously, which means a stone that reads well on paper can be a full grade or two softer in reality.
A report should be independent of the seller. If the only documentation is an in-house appraisal from the shop selling you the stone, you have a sales document, not a grading report.
For colored stones, ask specifically about treatment. Heated, diffused, oiled, fracture-filled, dyed, irradiated — each has different implications for durability and value, and each should appear in writing.
Conflict-free
The Kimberley Process was established to keep diamonds that fund armed conflict out of the legitimate supply chain, and it substantially reduced the trade in conflict stones. It is not a complete answer — it addresses conflict financing specifically rather than broader labor and environmental conditions — but it is the baseline, and any reputable supplier operates within it.
For full traceability, laboratory-grown diamonds sidestep the question entirely: a known origin, a known process, and a documented chain. Some mined sources also offer genuine traceability, including Canadian and certain Botswana production.
This applies beyond diamonds. Colored stone supply chains are longer and less regulated, which is one practical argument for buying from someone who sources personally and can tell you where a stone came from.
Cost
The third C is whether you understand what you paid for. A price is only meaningful when it is broken into parts: what the stone cost, what the metal cost, what the labor cost.
Sharon Teaman itemizes exactly that on every piece she makes — feature stone, carat weight and price, metal type, weight and price, side stones, total. It is unusual, and once you have seen a breakdown like that, an unexplained single number starts to look like what it is.
Frequently asked
Do I need a diamond certificate?
For any significant stone, yes, from a laboratory independent of the seller. Without one you are relying entirely on the seller's own grading.
Are lab-grown diamonds conflict-free?
Their origin is fully known and documented, which resolves the sourcing question directly. They are grown rather than mined, with a traceable process.
How do I know if a price is fair?
Ask for it broken down — stone, metal, labor. A seller who cannot or will not itemize is telling you something useful.
