A rare, uncut black diamond about the size of a golf ball and a magnificent tiara made of gold, sapphires and diamonds designed for Princess Charlene of Monaco are among the highlights at an upcoming exhibition by French jewellery house Van Cleef & Arpels at the ArtScience Museum.

The 340-carat black diamond is on loan from the French National Museum of Natural History.

As to its value, the president of the French museum told The Straits Times: "There is a difference between the value and the price. It has big value, but I don't know the price because we do not intend to sell it. It has big historical value and mineralogical value. It is something completely exceptional."

Meanwhile, the tiara, made with almost 900 diamonds and more than 300 sapphires, was a bridal gift from Prince Albert II of Monaco to his wife.

The tiara's design of asymmetrical circles was made to reflect the movement of water, since the princess was a former Olympic swimmer for South Africa.

The headpiece is on loan to Van Cleef & Arpels from the principality of Monaco for the four-month period of the exhibition.

These treasures are part of The Art & Science Of Gems, Van Cleef & Arpels' largest exhibition to date. It will showcase the artistry of the 110-year-old maison using more than 400 works from the brand's archives and pieces on loan from private collectors around the world.

The exhibits include jewellery owned by some of the world's most famous and beautiful women, such as Hollywood icon Elizabeth Taylor, American socialite and heiress Barbara Hutton and royal figures such as Her Royal Highness Princess Faiza of Egypt and the Duchess of Windsor, Wallis Simpson.

However, the show also has a twist to it. It includes elements of geoscience, so that besides viewing spectacular and intricate pieces of jewellery, visitors can also learn about the science behind the formation of these precious gems.

This is where the French National Museum of Natural History comes in.

The museum, which was founded in 1793, has provided more than 200 minerals and scientific artefacts for the exhibitionthat opens today and will run till Aug 14.

Mr Nicolas Bos, chief executive officer of Van Cleef & Arpels, told The Straits Times during a press conference in January: "Jewellery as decorative art is really a combination of artistic practice and the use of technique and craftsmanship. So there is this idea of science and technique associated with art."

In the exhibition, the raw uncut minerals and specimens have been paired alongside jewellery pieces that feature the corresponding processed jewels.

For example, bright orange and pink uncut topaz crystals sit alongside elegant, multi-faceted topaz stones.

Huge rough blocks of deep blue lapis-lazuli are contrasted with delicate bracelets and rings made from the same rocks.

While the scientific parts of the exhibition give insight into how water, temperature and pressure create beautiful stones, the rest of the show highlights what craftsmen do to turn these stones into exquisite jewellery and artworks.

To showcase the influences, styles and history of Van Cleef & Arpels, the exhibits have been split into seven themes, each presenting a different dimension of the maison.

In the Couture room, view pieces of gold lace embellished with rubies, inspired by the fashion of Paris.

Over at the Ballerinas And Fairies section, admire delicate brooches featuring Spanish dancers that capture dance movements in diamonds and emeralds.

One of the quirkier highlights under the theme Precious Objects, which showcases special orders made by the maison over the years, is a gold cage commissioned by an unnamed "Maharaja" in the 1930s for his pet frog.

Ms Catherine Cariou, heritage director of Van Cleef & Arpels, who was in Singapore this week (April 21)for the media preview of the exhibition, says the eccentric leader wanted a small ladder and pool in the cage for the frog.

Made of yellow gold, malachite, coral, onyx and rubies, the cage has since been transformed into a birdcage which hosts two lovebirds made of rose quartz.

In the Influences section, pieces inspired by various cultures and places, including China, Persia, Egypt, Mexico and Japan, fill the room.

One such piece is an Egyptianinspired bracelet made in 1924, which features hieroglyphic motifs such as scarabs and lotus flowers set with emeralds, sapphires, rubies, paved diamonds and onyx stones.

Mr Bos says: "I hope visitors will enjoy and learn and be enchanted. For those who have never seen a jewellery exhibition, I hope they will come out of it having discovered a fascinating and emotional new category."