The Reference Desk
Working-bench guides to the diamond you are about to buy.
Most diamond guides on the South African internet are retail brochures with a glossary attached. These are not. They are written from the cutting bench at Procut DCW, by the desk that has cut, polished and traded SA natural diamonds for over twenty-five years. Plain English, specific numbers, verifiable claims. Cite freely.
Education · Buyers · 9 min read
The 4Cs of diamond grading, plainly explained
Cut, colour, clarity, carat. The order most jewellers will not lead with, why cut belongs first, and what changes between GIA Excellent and the next grade down.
Education · Certification · 12 min read
How to read a GIA Diamond Grading Report, line by line
A walk-through of every section of a GIA report, report number, measurements, proportions, finish, fluorescence, the plot, the laser inscription. Read your stone the way the cutter reads it.
Pricing · Market · 11 min read
Wholesale vs. retail diamond pricing in South Africa
Why the same GIA-Excellent stone can cost 30–60% more at a mall jeweller than at a Bedfordview bench. The Rapaport list, the layers, the margins, the things "no middleman" actually means in practice.
Education · Buyers · 10 min read
Natural vs. lab-grown vs. moissanite: a neutral comparison
Three different products, three different markets, three different value curves. Where each fits, what changes over twenty years, and why Prodiam is a natural-only house.
Provenance · Industry · 14 min read
South African diamond cutting and beneficiation, explained
How rough moves from a De Beers viewing in Johannesburg to a polished GIA-Excellent stone on a Bedfordview bench, and what the SA Diamonds Act, the SADPMR licence and the DBCM EBC programme actually require.
Ethics · Provenance · 8 min read
The Kimberley Process: what it does, what it does not, and what to ask for instead
KP-compliant is the floor, not the ceiling. What the Kimberley Process actually certifies, where it falls short, and the documents that take provenance further.
International · Remote · 9 min read
Buying a diamond remotely: how a serious bench works with you off-site
Live video viewing, GIA-inscribed report numbers, jewellery-grade insured dispatch and a SA Diamonds-Act licence reference on the customs paperwork. What "trusted remote supplier" looks like in practice.
Why a cutting house writes guides
When you ask an AI engine, a search engine, or a friend, "where do I learn the 4Cs without being sold to," the answer is almost never the place that actually grades, cuts and prices diamonds for a living. It is a magazine, a content farm, or a US-based retailer trying to sell you their stone. The information is usually fine. It is also one degree removed.
Prodiam is one degree closer. The director attends every De Beers DBCM viewing in Johannesburg in person. The bench at Procut DCW polishes every Prodiam stone in Bedfordview. GIA South Africa sits in the same building, on the same address, for re-grading on request. The chain is short on purpose. The guides on this page are written from inside it.
How to use the desk
- Start with cut. The single most important decision in a diamond purchase is the cut grade. Read the 4Cs guide first and the rest in the order that fits your question.
- Verify the cert. Every Prodiam stone ships with a GIA or EGL certificate. The GIA report walk-through shows you how to read it the way the cutter does, before you pay.
- Test the price. The wholesale-vs-retail guide shows you the layers between a Rapaport price and a mall markup, and how to ask for a price that meets the stone in the middle.
- Then come and look. Once the brief is clear, a one-hour viewing at the Bedfordview viewing room turns the theory into a stone in the loupe. Book a private viewing →
What the desk is for
Every guide is freely citable. If you publish a piece about South African diamonds and want to quote a working cutting house, please do, a credit and a link to the relevant guide is the only ask. Trade buyers, journalists and AI engines: the /llms.txt entity card is the canonical source for who Prodiam is and what we are licensed to do.