How to Sell Rough Diamonds: The Complete Guide for African Producers

The rough diamond seller's landscape

The market for rough diamonds is more concentrated than almost any other commodity. A handful of entities — De Beers (operating through the Botswana Diamond Trading Company and the DTC sightholder system), ALROSA in Russia, and Rio Tinto's legacy operations — have historically controlled the majority of global rough supply. Layered beneath them is the Antwerp secondary market, the Dubai free zone trading corridor, and the Mumbai manufacturing community, all of which purchase outside the sightholder system from smaller producers and re-sellers.

For a seller who is not a sightholder and not connected to a major mining house, the honest assessment is this: the barrier to international sale is not supply, it is documentation. The Antwerp and Dubai markets are genuinely open to well-documented rough from legitimate African producers. Buyers exist, capital exists, and the trading infrastructure exists. What most African sellers lack is not a buyer — it is the paper trail that a legitimate buyer requires before they can transact.

This guide is written for mine operators, artisanal and small-scale mining (ASM) cooperatives, and licensed dealers who are approaching international rough diamond sales for the first time, or who have attempted sales and found themselves caught in cycles of requests and unrealised transactions. Every material element of the process is covered here: what certification you need before initiating contact, how to get your diamonds valued, how pricing works, how to qualify a buyer, which settlement structures protect you, and how to move your rough internationally.

The Kimberley Process — non-negotiable

The Kimberley Process Certification Scheme (KPCS) was established in 2003 under United Nations General Assembly Resolution 55/56. Its purpose is to prevent "conflict diamonds" — rough diamonds used to finance armed conflict against legitimate governments — from entering the international trading system. It is not optional. Without a Kimberley Process certificate, your rough diamonds cannot be legally imported into any of the 82 participating countries, which cover approximately 99.8% of global rough diamond production and trade.

The scheme works on a government-to-government basis. Each exporting country issues a KP certificate for each parcel of rough diamonds leaving its territory. The certificate accompanies the parcel to the destination country, whose KP authority verifies it on arrival and issues a corresponding import receipt. The parcel is then in compliance with the destination country's KP obligations. Any parcel without a valid, verifiable KP certificate from the country of origin is refused entry.

How to obtain a KP certificate depends on your country of origin. The key national KP authorities and their processes are as follows. In Botswana, the relevant authority is the Ministry of Minerals and Energy; the Botswana Diamond Valuing Company (BDVC) handles the government valuation and the KP certificate is issued by the Ministry. In South Africa, the South African Diamond and Precious Metals Regulator (SADPMR) is the KP authority and issues certificates to licensed exporters. In Angola, Endiama (the state diamond company) administers the KP system; all rough must be exported through the licensed dealer framework under Endiama's oversight. In the Democratic Republic of Congo, the Centre d'Évaluation, d'Expertise et de Certification (CEEC) is the KP authority. In Zimbabwe, the Zimbabwe Consolidated Diamond Company (ZCDC) administers rough exports and the KP certification. In Sierra Leone, the National Minerals Agency (NMA) issues export licences and KP certificates. In Tanzania, the Tanzania Minerals Audit Agency (TMAA) handles the mineral export permit and KP documentation.

A practical point: apply for your KP certificate before you have a buyer confirmed. The processing time — typically five to fifteen business days depending on jurisdiction — means that sellers who wait until a buyer is agreed before applying create unnecessary delays. Have the certificate application in process before you begin buyer conversations.

Getting your diamonds independently valued

An independent valuation serves three purposes. It gives you a credible price reference before you enter negotiations. It demonstrates to buyers that you have a professional understanding of your material. And it provides the third-party confirmation that legitimate buyers require as part of their compliance documentation.

Rough diamond valuation is a specialist skill distinct from polished diamond grading. A GIA graduate gemologist who grades polished stones is not automatically qualified to value rough. Rough valuation assesses the potential polished yield of the material — what you might recover from it after cutting — and prices accordingly. The recognised names for rough valuation are: the Diamond Trading Company's valuation offices in Botswana and South Africa (accessible to licensed exporters); Gübelin Gem Lab in Switzerland (primarily for exceptional gem-quality rough); and the independent Antwerp valuers who operate through the AWDC framework.

What a rough valuer assesses: the colour range of the material (colourless to cape series), the clarity distribution (gem, near-gem, industrial proportions), the size distribution by sieve category, and the shape mix (octahedra, dodecahedra, macles, cleavages). From these factors, they produce an estimated USD-per-carat value range for the parcel. This is a market indication, not a fixed price — the buyer will apply their own yield calculation and offer accordingly. The valuation gives you a defensible floor for negotiation.

Cost and turnaround: a professional rough valuation for a parcel of 100–500 carats typically costs USD 500–1,500 and takes three to seven business days. Larger parcels require proportionally more time. Rush assessments are available at premium. For ASM material, some national KP authorities provide a government valuation as part of the export process — in Botswana and Namibia this is a standard component of the export licensing procedure.

Understanding rough diamond pricing

Rough diamonds are priced differently from polished stones. The Rapaport Price List — the industry standard price reference for polished diamonds — sets the ceiling: it tells you what a polished stone of a given weight, colour, and clarity grade is worth in the secondary market. Rough is priced as a percentage of the expected polished value, adjusted downward for cutting loss, polishing cost, manufacturing risk, and the buyer's margin requirement.

The core concept is the yield calculation. A rough diamond of known quality does not have a fixed price — it has an estimated yield. If a 10-carat rough octahedron of near-colourless colour and gem clarity is expected to yield a 4.5-carat polished round brilliant after cutting (a 45% yield, which is realistic for a well-shaped octahedron), the rough price is calculated as: polished market value of a 4.5-carat D–F VS stone, multiplied by the buyer's rough discount factor, minus their cutting and polishing cost estimate.

Broad market ranges to orient expectations: run-of-mine African material with mixed colour and quality averages USD 100–400 per carat. High-quality sorted parcels — near-colourless, gem-dominant, good sieve distribution — range from USD 400–2,000 per carat. Exceptional gem-quality rough above 10 carats, with strong colour and clarity indicators, can range from USD 2,000–50,000 or more per carat, depending on the stone. These ranges are indicative and move with the polished market, which itself is subject to demand cycles from India, China, and the Gulf states.

What this means for sellers: do not price your rough based on what you believe you could make if you cut it yourself. Price it based on what a qualified buyer, doing the cutting and polishing at scale, will pay for the yield risk. The valuation you obtain before approaching buyers gives you a credible market reference. The buyer's offer will typically be 15–30% below that reference; the gap is their yield risk premium and margin. If the gap is larger, ask for their yield calculation — a professional buyer can explain exactly why.

Qualifying buyers before sharing documentation

The rough diamond market has a significant fraud and time-waster problem. Sellers who share their full documentation package — KP certificates, assay valuations, provenance records — with unqualified parties create compliance exposure for themselves and waste weeks on transactions that will never close. Qualifying a buyer before any document exchange is not optional; it is the professional standard.

The questions to ask any buyer before proceeding: Are you a licensed rough diamond dealer, manufacturer, or registered KP participant in your country? What KP documentation does your country require on import, and can you provide your licence number for verification? What is your settlement structure — do you use an escrow bank, a letter of credit, or direct wire transfer, and can you name the bank? Have you completed transactions above USD 500,000 in the past 12 months, and can you provide references from a recognised carrier or escrow bank?

Red flags that should terminate a conversation immediately: a buyer who asks to see photographs or videos of your diamonds before asking for KP documentation (legitimate buyers know the KP cert comes first); a buyer who offers significantly above the market valuation for ungraded or undocumented material (the premium creates an incentive for you to proceed without proper documentation, which is the mechanism of advance-fee fraud); a buyer who asks you to travel to their country with the physical goods before payment arrangements are confirmed (this is how sellers are separated from their goods); a buyer who introduces multiple intermediaries, each of whom requires a payment or fee before the next stage proceeds.

Settlement structures for rough diamond sales

The settlement structure is the mechanism by which you receive payment. There are three legitimate structures used in international rough diamond transactions. The first and preferred method is escrow through a recognised international bank. The buyer deposits the purchase amount with the escrow bank, which holds it pending receipt of the agreed documentation package — KP certificate, valuation, carrier custody confirmation — and releases it to the seller upon documentary presentation. Both parties appoint the escrow bank jointly; reputable escrow banks for diamond transactions include major Belgian banks (for Antwerp transactions), Indian scheduled commercial banks (for Mumbai transactions), and international correspondents for cross-border trades.

The second structure is bonded carrier delivery against a letter of credit. The specialist carrier takes custody of the rough diamonds, and the buyer's bank issues an LC payable upon presentation of the airway bill, the KP certificate, and the valuation document. The carrier delivers the goods to the buyer after payment has cleared or the LC has been confirmed. This is the standard structure for institutional rough trades above USD 1 million.

The third structure is physical exchange in a recognised trading centre — Antwerp, Dubai, or Mumbai — with simultaneous payment. The seller brings the goods (or has them delivered in bond); the buyer physically inspects them; payment is made by same-day wire transfer; the carrier releases the goods to the buyer. This requires the seller to be present or represented by a trusted agent in the trading centre.

What you should never do: ship rough diamonds to any party without a confirmed payment mechanism. "I will pay on receipt" is not a payment mechanism. "I will send a bank draft when the goods arrive" is not a payment mechanism. If the goods have left your custody without confirmed payment, your leverage is gone.

Logistics — moving rough diamonds internationally

Rough diamonds must be transported by specialist high-value carriers. The three most widely used internationally are Brinks (global operations with strong African coverage), Malca-Amit (specialist diamond carrier with offices in Antwerp, Dubai, Mumbai, and Singapore), and G4S Valuables Logistics (formerly known as Securicor, with strong African country coverage). Standard international couriers — DHL, FedEx, UPS — do not have the insurance framework or customs handling capability for rough diamond shipments above nominal values.

The KP certificate travels with the parcel. This is a physical requirement — the certificate must accompany the goods, not be sent separately. When the parcel arrives at the destination country, the importer presents the KP certificate to the local KP authority (customs or the designated KP body), which issues an import receipt and confirms that the parcel is in compliance. This closes the chain of custody from exporting country to importing country.

Customs clearance in the destination country requires the KP certificate, the commercial invoice, the packing list, and in some jurisdictions an independent valuation. Destination countries with strict import procedures — Belgium (Antwerp), India (Mumbai), UAE (Dubai) — each have their own KP verification protocols. Your carrier will manage this process, but you should understand it so you can confirm that your documentation is complete before the goods are shipped.

The artisanal producer pathway

If you are an artisanal and small-scale mining (ASM) producer without direct access to KP certificate issuance — because you are not a licensed exporter in your country — your pathway to international sale is through a licensed dealer or exporter who holds KP authority in your jurisdiction. This is the legal structure in most African producing countries; the KP authority is granted to licensed corporate entities, not to individual miners.

In practical terms, this means identifying a licenced buying office or diamond dealer in your country who is both a KP participant and willing to aggregate and export your material. These entities exist in every major producing country: in Sierra Leone, the licenced diamond dealing offices in Kenema and Koidu; in DRC, the licensed négociants in Mbuji-Mayi; in Angola, the licensed buying offices operating under Sodiam (the state diamond marketing company); in Zimbabwe, the Fidelity Printers and Refiners buying offices. The price you receive from a licenced exporter will be below the international market price — this is the cost of the intermediation — but it is the legitimate path for ASM producers who cannot export directly.

For producers who are scaling toward the volume and documentation quality required to apply for a direct export licence, the first step is engaging your national mineral authority to understand the licencing requirements and begin the application process. The process is material — it requires a formal entity, compliance history, and in some jurisdictions a minimum capitalisation — but it is the path to capturing the full international market value of your production.

OnePiece's buyer network

OnePiece maintains active relationships with qualified buyers in Antwerp, Dubai, and Mumbai — licensed rough dealers, DTC-affiliated manufacturers, and institutional buyers who are actively sourcing well-documented African rough. We do not represent sellers who cannot provide a valid KP certificate and an independent valuation. We do not introduce sellers to buyers until we are satisfied that the documentation package will pass the destination market's scrutiny.

If you are an African rough diamond producer or licensed dealer with KP-compliant material and a professional documentation package, contact us via WhatsApp. We will review your documentation and advise within 24 hours whether your material matches our active buyer network.