Celeb Engagement Rings (PHOTOS); Halle Berry engagement ring has hidden code. Olivier Martinez has confirmed his engagement to Halle Berry.

The 46-year-old French actor - who met Halle on the set of 'Dark Tide' in 2010 - has finally gone public with their plans to marry.

"The ring is textured and contains codes and symbols which you cannot see," says Martinez, "only the person wearing it can."

Martinez reportedly took an "alchemy test" to help with the design of Halle Berry's engagement ring.

The actor was apparently ordered to take the 500-year-old mystical quiz by Paris-based jeweller Robert Mazlo, who he turned to to create the yellow gold and emerald ring.

According to a source, Olivier had to answer seven questions about his 'Dark Tides' co-star's favourite shapes, colours, numbers and signs, which Robert "decoded" and used to perfect the ring.

The insider told US Weekly: "Olivier was absolutely delighted with the result."

It is not yet known when or where Olivier and 45-year-old Halle – who has daughter Nahla, three, with ex-boyfriend Gabriel Aubry and was previously married to baseball player David Justice and singer Eric Benet - will tie the knot.

However, his home county of France is said to be in the frame.

The source added: "[Plans are] not yet finalised, [but there's a] very good chance it would be in Paris. It will be first time round for Olivier … he would love it to be in his home city – the city he knows and loves."

It will be the first marriage for Olivier - who has previously dated Kylie Minogue and Rosie Huntington-Whiteley. Halle, 45 - who has daughter Nahla, three, with ex-boyfriend Gabriel Aubry - was married to former baseball player David Justice from 1993 to 1997 and to singer Eric Benet from 2001 to 2005. (c) BANG

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