4. Christie's European Jewellery Director Raymond Sancroft-Baker holding diamond
5. SOUNDBITE (English) Raymond Sancroft-Baker, European Jewellery Director at Christie's:
"It's a fantastic stone, not only is it 14-and-a- half carats which is a good size, but it is vivid blue, which is the best possible colour you can have. And it's estimated fetch in the region of 40 (m) million (US) dollars - will certainly be a record for that type of diamond. There's been several other blue diamonds which have been sold in the past, but nothing really quite of this quality."
6. "Oppenheimer Blue" diamond in cabinet
7. SOUNDBITE (English) Raymond Sancroft-Baker, European Jewellery Director at Christie's:
"It got a fabulous name to it, of course, the "Oppenheimer" diamond, it was owned by Sir Philip Oppenheimer who acquired it really from the De Beers mine, because he owned the Cullinan Mine in South Africa in probably the 1950s. So he had the pick of all diamonds over a fifty year period, and this is what he picked out for his wife. So, it's a very significant stone with a lovely provenance, and it's VVS1 which means it is nearly perfect, it's not internally flawless, but Christie's are really proud to be offering such a stone."
8. Jewellery on display ahead of Christie's auction
10. Fancy vivid orange-yellow "Oriental Sunrise" earrings in cabinet
11. Christie's Jewellery presentation
12. Preparations in auction room
13. Security at entrance of "Hotel des Bergues" where auction takes place
14. Entrance of hotel
15. Geneva's landmark "Jet D'eau" fountain on Lake Geneva