Our Team
The Board
Sandrine Conseiller - Chair
CEO, De Beers Brands (Brands & Consumer Markets) & member of the De Beers Executive Committee
Sandrine joined De Beers from Maus Freres Brands Group, where for almost eight years she held the role of CEO, Aigle (an outdoor clothing and accessories brand) and previously the role of Group Marketing & Branding Executive Vice President for Lacoste. Prior to this, and throughout her career, she has held senior leadership roles in Marketing, General Management and Audit disciplines across various geographies when working for Unilever.
She holds a Master’s in Business Management from NEOMA Business School and has an International Directors Programme Certificate from INSEAD. She had the honor of receiving the Chevalière de l’Ordre National du Mérite (Knight of the French Republic) in recognition for promoting diversity in business while developing sustainability within the French industry.
Sandrine has served as Board Member and Senior Advisor, including at PPYarns, Carbios and Raise Sherpas.
Outside of her professional life, Sandrine enjoys time with her friends and especially her family.
Sandrine Conseiller - Chair
CEO, De Beers Brands (Brands & Consumer Markets) & member of the De Beers Executive Committee
Sandrine joined De Beers from Maus Freres Brands Group, where for almost eight years she held the role of CEO, Aigle (an outdoor clothing and accessories brand) and previously the role of Group Marketing & Branding Executive Vice President for Lacoste. Prior to this, and throughout her career, she has held senior leadership roles in Marketing, General Management and Audit disciplines across various geographies when working for Unilever.
She holds a Master’s in Business Management from NEOMA Business School and has an International Directors Programme Certificate from INSEAD. She had the honor of receiving the Chevalière de l’Ordre National du Mérite (Knight of the French Republic) in recognition for promoting diversity in business while developing sustainability within the French industry.
Sandrine has served as Board Member and Senior Advisor, including at PPYarns, Carbios and Raise Sherpas.
Outside of her professional life, Sandrine enjoys time with her friends and especially her family.
Patrick Coppens - Vice Chair
General Manager, Sales and Marketing, Rio Tinto
Patrick has served as General Manager of Sales and Marketing for Rio Tinto’s Diamonds business for almost 14 years. He holds a Graduate Degree in Diamonds and Diamond Grading from the Gemological Institute of America (GIA) and is a qualified Investment Adviser from the EHSAL Management School in Brussels. He has more than 30 years of experience in rough and polished diamond sales, marketing, and business development, having been closely involved in the commercialization of diamond mines across different continents. Patrick is based in Antwerp, Belgium, and has worked across a global diamond portfolio from mine to market that has included Australia, Canada, Africa, China, Japan, the US, and Europe.
Patrick Coppens - Vice Chair
General Manager, Sales and Marketing, Rio Tinto
Patrick has served as General Manager of Sales and Marketing for Rio Tinto’s Diamonds business for almost 14 years. He holds a Graduate Degree in Diamonds and Diamond Grading from the Gemological Institute of America (GIA) and is a qualified Investment Adviser from the EHSAL Management School in Brussels. He has more than 30 years of experience in rough and polished diamond sales, marketing, and business development, having been closely involved in the commercialization of diamond mines across different continents. Patrick is based in Antwerp, Belgium, and has worked across a global diamond portfolio from mine to market that has included Australia, Canada, Africa, China, Japan, the US, and Europe.
Richard Duffy
Chief Executive Officer, Petra Diamonds Limited
Richard has spent more than 30 years working in the global mining industry, initially with Anglo American plc and then AngloGold Ashanti Limited, since its inception in 1998. In 2008, he was appointed Executive Vice President of Africa Region and continued in this role until January 2010 when he began overseeing operations in Namibia, Tanzania, Guinea, Ghana, and Mali and a joint venture in the Democratic Republic of the Congo. In 2013, Richard was appointed Chief Financial Officer and was tasked with overseeing all financial matters, including the formulation and execution of financial business strategy, debt and equity financing. In 2015, Richard became the Co-Founder and Director of Africa Energy Management Platform, a private energy company targeting industrial and mining clients in sub-Saharan Africa. He joined Petra Diamonds as CEO in April 2019.
Richard Duffy
Chief Executive Officer, Petra Diamonds Limited
Richard has spent more than 30 years working in the global mining industry, initially with Anglo American plc and then AngloGold Ashanti Limited, since its inception in 1998. In 2008, he was appointed Executive Vice President of Africa Region and continued in this role until January 2010 when he began overseeing operations in Namibia, Tanzania, Guinea, Ghana, and Mali and a joint venture in the Democratic Republic of the Congo. In 2013, Richard was appointed Chief Financial Officer and was tasked with overseeing all financial matters, including the formulation and execution of financial business strategy, debt and equity financing. In 2015, Richard became the Co-Founder and Director of Africa Energy Management Platform, a private energy company targeting industrial and mining clients in sub-Saharan Africa. He joined Petra Diamonds as CEO in April 2019.
Mmetla Masire
Managing Director, Okavango Diamond Company
Mmetla Masire was appointed ODC Managing Director in July 2021. Mr. Masire has over 30 years of experience in the diamond industry. He joins ODC, from the Ministry of Mineral Resources, Green Technology & Energy Security where he served as Permanent Secretary. Some of the senior positions he has held include being the CEO of Water Utilities Corporation, Debswana Group Engineering Manager, Orapa Power Station Project Manager, and Mine General Manager. Mr. Masire holds a Bachelor of Engineering (BEng) in Electrical & Electronics from the University of Wales. Mr. Masire has served on several boards including De Beers, Debswana, Diamond Trading Company Botswana, Minerals Development Company Botswana, etc. He is currently the Chairman of the Board of Trustees of Sir Ketumile Masire Foundation and the President of Botswana Cycling Association.
Mmetla Masire
Managing Director, Okavango Diamond Company
Mmetla Masire was appointed ODC Managing Director in July 2021. Mr. Masire has over 30 years of experience in the diamond industry. He joins ODC, from the Ministry of Mineral Resources, Green Technology & Energy Security where he served as Permanent Secretary. Some of the senior positions he has held include being the CEO of Water Utilities Corporation, Debswana Group Engineering Manager, Orapa Power Station Project Manager, and Mine General Manager. Mr. Masire holds a Bachelor of Engineering (BEng) in Electrical & Electronics from the University of Wales. Mr. Masire has served on several boards including De Beers, Debswana, Diamond Trading Company Botswana, Minerals Development Company Botswana, etc. He is currently the Chairman of the Board of Trustees of Sir Ketumile Masire Foundation and the President of Botswana Cycling Association.
Natural Diamond Council Executive Team
David Kellie
David Kellie, Chief Executive Officer, has more than 30 years of experience in leading marketing campaigns for some of the most influential brands around the world. David previously oversaw the marketing launch of the UK’s largest luxury timepiece retailer, Watches of Switzerland Group, into the US. Prior to that, he spent 15 years with Ralph Lauren initially in Geneva, Switzerland and then in New York where he led the global marketing and advertising teams across the full portfolio of brands and business. David currently lives in New York.
David Kellie
David Kellie, Chief Executive Officer, has more than 30 years of experience in leading marketing campaigns for some of the most influential brands around the world. David previously oversaw the marketing launch of the UK’s largest luxury timepiece retailer, Watches of Switzerland Group, into the US. Prior to that, he spent 15 years with Ralph Lauren initially in Geneva, Switzerland and then in New York where he led the global marketing and advertising teams across the full portfolio of brands and business. David currently lives in New York.
Katja Thoelen
Katja Thoelen, Chief Financial Officer, has worked with global companies across several industries for more than two decades. Katja is responsible for managing finance, accounting, legal, tax and human resources. Katja has held senior positions at Xella, DME Europe, ITAB Shop Concept, British Petroleum Belgium, and currently lives in Antwerp, Belgium.
Katja Thoelen
Katja Thoelen, Chief Financial Officer, has worked with global companies across several industries for more than two decades. Katja is responsible for managing finance, accounting, legal, tax and human resources. Katja has held senior positions at Xella, DME Europe, ITAB Shop Concept, British Petroleum Belgium, and currently lives in Antwerp, Belgium.
Kristina Buckley Kayel
Kristina Buckley Kayel, Managing Director & CMO of North America, steers Only Natural Diamonds, the consumer-facing editorial platform, advertising campaigns, trade and retail partnerships, education, press, and consumer insights. Kristina oversaw marketing and communications at Van Cleef & Arpels for over a decade. She has also held senior marketing roles at Baccarat, Bottega Veneta, and Ferragamo. Kristina currently lives in New York.
Kristina Buckley Kayel
Kristina Buckley Kayel, Managing Director & CMO of North America, steers Only Natural Diamonds, the consumer-facing editorial platform, advertising campaigns, trade and retail partnerships, education, press, and consumer insights. Kristina oversaw marketing and communications at Van Cleef & Arpels for over a decade. She has also held senior marketing roles at Baccarat, Bottega Veneta, and Ferragamo. Kristina currently lives in New York.
Sissi Xu
Sissi Xu, the Managing Director for Greater China at the Natural Diamond Council, directs the strategic planning and execution of marketing, communication, social and digital strategy, training, and education. She proactively initiates collaborative efforts with retail and trade partners, driving the establishment and nurturing of key retail partnerships in the Chinese market. With nearly two decades of extensive expertise, Sissi has consistently demonstrated excellence in marketing communication and brand promotion. Before joining NDC, Sissi dedicated 5 years to The LEGO Group, leading retail management and shopper marketing. Preceding this, she spent 7 years with SEPHORA China, an esteemed cosmetics retail brand under the French luxury group LVMH, where she oversaw marketing communication, retail activation, PR, and events.
Leveraging her profound knowledge of the luxury goods and lifestyle industry, coupled with an insightful understanding of Chinese millennial consumers, Sissi Xu, with a wealth of leadership experience, leads the NDC Chinese team in championing the natural diamond dream among Chinese consumers.
Sissi Xu
Sissi Xu, the Managing Director for Greater China at the Natural Diamond Council, directs the strategic planning and execution of marketing, communication, social and digital strategy, training, and education. She proactively initiates collaborative efforts with retail and trade partners, driving the establishment and nurturing of key retail partnerships in the Chinese market. With nearly two decades of extensive expertise, Sissi has consistently demonstrated excellence in marketing communication and brand promotion. Before joining NDC, Sissi dedicated 5 years to The LEGO Group, leading retail management and shopper marketing. Preceding this, she spent 7 years with SEPHORA China, an esteemed cosmetics retail brand under the French luxury group LVMH, where she oversaw marketing communication, retail activation, PR, and events.
Leveraging her profound knowledge of the luxury goods and lifestyle industry, coupled with an insightful understanding of Chinese millennial consumers, Sissi Xu, with a wealth of leadership experience, leads the NDC Chinese team in championing the natural diamond dream among Chinese consumers.
Raluca Anghel
Raluca Anghel, Head of External Affairs and Industry Relations, is responsible for global external engagement and public affairs, while also spearheading communication and marketing efforts in Europe. Raluca skilfully coordinated Microsoft’s European storytelling agenda before transitioning to the European Parliament. There, she excelled in leading public relations campaigns and crafting policies related to vital areas such as social affairs, SME growth and technology. Raluca has held the role of Spokesperson for the Romanian Presidency of the European Union Council. With an extensive 11-year tenure in Brussels, she now lives in the UK.
Raluca Anghel
Raluca Anghel, Head of External Affairs and Industry Relations, is responsible for global external engagement and public affairs, while also spearheading communication and marketing efforts in Europe. Raluca skilfully coordinated Microsoft’s European storytelling agenda before transitioning to the European Parliament. There, she excelled in leading public relations campaigns and crafting policies related to vital areas such as social affairs, SME growth and technology. Raluca has held the role of Spokesperson for the Romanian Presidency of the European Union Council. With an extensive 11-year tenure in Brussels, she now lives in the UK.
Richa Singh
Richa Singh, Managing Director of India and Middle East, has worked in luxury marketing for over 25 years. An innovative strategist, Richa has a deep understanding of the luxury consumer landscape and leads the execution of consumer and partner-facing activations aimed at boosting the natural diamond category. Richa has held senior positions at L’Oreal where she helped scale up and build brands across diverse categories encompassing beauty and luxury products. Richa currently lives in Mumbai, India.
Richa Singh
Richa Singh, Managing Director of India and Middle East, has worked in luxury marketing for over 25 years. An innovative strategist, Richa has a deep understanding of the luxury consumer landscape and leads the execution of consumer and partner-facing activations aimed at boosting the natural diamond category. Richa has held senior positions at L’Oreal where she helped scale up and build brands across diverse categories encompassing beauty and luxury products. Richa currently lives in Mumbai, India.
