Francois Graff: I had to lose 100 carats of impure diamond surrounding the perfection that was left. Today, collectors want something really so extraordinary that they can probably safely say that it will be never done again in their lifetime , or their children's lifetimes.
Maria Doulton: Chaumet celebrates water in its many forms with the Lumières d'Eau jewels. What's interesting is that it hasn't used the obvious blue, but have instead explored the many forms of water, and I particularly like those that are frozen. It's captured in diamonds , opals and rock crystal.
Cartier Royale focuses on exceptional, supersized and even historical stones. This cornflower blue ring has a sapphire of almost 30 carats and is said to be one of the finest of its kind in the world, due to its colour and size. I've decided to show you this bracelet because it has a completely natural, untreated tanzanite at its centre .
For me, one of the highlights of the show is this Boucheron brooch, which was shown at the original 1925 exhibition in Paris of Arts Décoratifs that in fact gave art deco its name. Lee Siegelson tells us more.