Not every diamond is destined for jewelry. In fact, about are unsuitable for adornment due to heavy inclusions or poor color. These "boart" or industrial-grade stones are purchased by companies in the tooling, drilling, and tech sectors. Because diamonds are the hardest known natural material, they are essential for industrial cutting, grinding, and polishing tools. 5. High-End Jewelry Maisons
Middlemen play a vital role in the "secondary market." These traders buy rough parcels from smaller mines or at auctions and break them down into smaller, more specific lots. They then sell these tailored packages to smaller manufacturers who may only need specific sizes or qualities of stones. 4. Industrial Buyers who buys rough diamonds
While some Sightholders cut their own stones, many other rough diamonds are sold to independent manufacturing firms, primarily located in global hubs like (where roughly 90% of the world's diamonds are cut) and Antwerp, Belgium . These buyers are experts in "planning" a stone—using 3D scanning technology to decide how to cut a rough crystal to maximize its weight and clarity. 3. Professional Traders and Wholesalers Not every diamond is destined for jewelry
The journey of a rough diamond from the earth to a ring finger involves a specialized group of buyers. These players operate in a high-stakes market where value is determined by potential rather than immediate sparkle. 1. Large-Scale Sightholders Because diamonds are the hardest known natural material,
A small, elite group of luxury brands—such as Tiffany & Co., Graff, and Harry Winston—occasionally buy exceptional, "special" category rough stones. By purchasing a massive rough diamond directly, these houses can oversee the entire provenance and cutting process to ensure the final gem meets their specific brand standards for "perfection." 6. Specialized Investors