Home | Bonas Group MENU Tender & Auction Sales Diamonds Why Bonas? Service Sorting & Valuation Infrastructure Online Platform Mining Partners Traceability Special Events Gemstones Service Infrastructure Remote Deployment Transparency & Compliance Mining Partners Sugilite Creating a Market Sugilite Hong Kong Viewings Online Platform Transparency & Compliance Value Chain Consulting Industry Reporting & Consulting Pricing Analysis & Trends Marketing & Branding Services De Beers Relationship Management Overview Introduction & Profile Raising Facilitation & Intermediation Business Compliance Brokerage Services About Bonas History & Philosophy People Industry Leadership Responsibility RJC Founding Partner JINC BE Contact Information Sales Calendar Policies UPCOMING AUCTIONS, TENDERS & EVENTS BUYER REGISTRATION EN PT EN PT Upcoming VIEW ALL EVENTS 21 28Aug August 2026 Tender CDM-2607 Petra Diamonds ORIGIN: South-Africa Rough Diamonds Antwerp viewings Closing: 28 August 2026 5pm ADD TO CALENDAR MiningPartners About Bonas Bonas is the world’s longest established diamond brokerage and consultancy firm. More recently, it has also become the largest global independent diamond and gemstone tender and auction house. From its position at the forefront of value chain consulting, Bonas is able to help shape the future prosperity and sustainability of the diamond and gemstone industries. The firm is proud to count many of the world’s most important diamantaires as clients, who between them produce a significant part of the global polished diamond output. A fifth generation, family-owned firm, Bonas combines stability in a shifting industry with the expertise and agility to anticipate and embrace change. 45 Sale Events Hosted in 2025 12 Direct-From-Mine Productions over 5 Million Cts Sold in 2025 (All Gemstones) Services Tender & Auction Sales Regularly organising diamond and gemstone sales on behalf of publicly-listed and private mining companies, as well as private sellers. Find Out More Value Chain Consulting Industry reporting and consulting across the diamond and gemstone pipelines. Find Out More De Beers Relationship Management Assisting clients in optimising direct rough diamond supplies and commercial opportunities with De Beers Group of Companies. Find Out More UPCOMING AUCTIONS, TENDERS & EVENTS BUYER REGISTRATION ANTWERP LONDON GABORONE JOHANNESBURG DUBAI MUMBAI HONG KONG Tender & Auction Sales Diamonds Why Bonas? Service Sorting & Valuation Infrastructure Online Platform Mining Partners Traceability Special Events Gemstones Service Infrastructure Remote Deployment Transparency & Compliance Mining Partners Sugilite Creating a Market Sugilite Hong Kong Viewings Online Platform Transparency & Compliance Value Chain Consulting Industry Reporting & Consulting Pricing Analysis & Trends Marketing & Branding Services De Beers Relationship Management Overview Introduction & Profile Raising Facilitation & Intermediation Business Compliance Brokerage Services About Bonas History & Philosophy People Industry Leadership Responsibility RJC Founding Partner JINC BE Contact Information Sales Calendar Policies PROUD MEMBER OF : © 2026 Bonas Group Privacy Notice Terms and Conditions Cookie preferences MiningPartners