A collection of precious jewellery amassed by Italian actress, photojournalist and sculptor Gina Lollobrigida, now aged 85, is to auction at Sotheby's Geneva on May 14.

Gina Lollobrigida pictured at the Cannes film festival in 1991

Key pieces from the collection include a circa 1962 19 carat diamond ring estimated to be worth $1m, a pair of circa 1964 diamond and pear pendant earrings also valued at $1m, and a 1954 diamond encrusted necklace/bracelet combination, which has been given a $500,000 estimate.

Commenting on the sale, Lollobrigida said: "I have been lucky enough to have been given many roles in my life - as an actor, a mother, a photojournalist, an ambassador for FAO, and as an artist.

"A sculptor has little need for jewels, and so, I have decided the time is right to share them with other collectors. In doing so, I can also help a cause that is very close to my heart, that of stem cell research - treatment which I believe should be freely available to every child."

For more information on the investment potential of the jewellery market, see Paul Fraser Collectibles' free guide to investing in watches and jewellery.

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