Pierres de Caractère: an exploration of Earth's Treasures

“Every stone has a soul of its own,” Claude Arpels used to say.
For over a century, exceptional stones – or ‘Pierres de Caractère’ - have been at the centrepiece of Van Cleef & Arpels’ creativity. From diamonds to coloured gems, the Maison seeks excellence but also character, that spiritual quality which awakens the senses and instils a unique emotion. 

Dive into the earth and meet its treasures, discovering the origin and evolution of the ‘big four’ precious stones – emerald, ruby, diamond and sapphire – observed through the eyes of noted jewellery and stones experts Joanna Hardy and Olivier Segura.

Joanna Hardy (Independent Fine Jewellery Specialist)
Olivier Segura (Gemologist and Scientific Director at L’ÉCOLE, School of Jewellery Arts)

Joanna Hardy is an independent fine jewellery specialist with over 35 years’ experience working in the jewellery industry. She began her career training as a goldsmith at Sir John Cass College before working as a rough diamond valuer and grader for De Beers. She then became one of the first women to be a polished diamond dealer in Antwerp and then joined Philips the Auctioneers in London. She moved on to Sotheby’s in Bond Street, London  and was their senior jewellery specialist and auctioneer for fourteen years and since 2009 has worked independently. Joanna is accredited lecturer for The Arts Society  and writes articles for publications worldwide and is a published author with her books, 'Collect Contemporary Jewelry', ‘Emerald’, ‘Ruby’ and ‘Sapphire‘ published by Thames and Hudson and a contributing author to ‘Graff’ published by Rizzoli and ‘Cartier Panthère published by Assouline. She curates contemporary jewellery exhibitions, has a foundation jewellery course with the online platform Learningwithexperts.com and is the curator for the Omnēque.com antique and contemporary jewellery selling platform.

Olivier Segura is the Scientific Director of L’ÉCOLE, School of Jewelry Arts, supported by Van Cleef & Arpels. He has a unique academic and professional background, blending diverse skills, each of which have contributed to his success in the gem and jewelry field. He holds two degrees from Paris University, an MSc in Biology and Geology and a Master’s degree in Marketing and Communications; a Graduate Gemologist (GG) certification from GIA; a DUG from Nantes University on the orange luminescence of gem corundum (2012) and field experience in various parts of the world, including extensive time in Burma, deepening his knowledge of gem markets and developing relationships with key people at important mining operations. From 2011 to 2018, Segura was Director of the LFG (French Gemological Laboratory) based in Paris – France – and he has focused his skills on raising the professional standards of the laboratory to new heights, expanding staff, adding more sophisticated instrumentation, and managing a team of gemologists working on diamonds, colored gemstones and pearl testing. He also developed a School of gemology and welcomed many students every year. He regularly takes part in conferences and is a featured lecturer on a variety of gemological topics. Segura is also involved in various international organizations as a French delegate for CIBJO and Vice president of the CIBJO Pearl Commission; Member of the RJC communication committee; and French representative for the ISO jewelry standards. Since June 2020, he is also the President of the French Gemology Association (AFG).
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