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On Thursday, the Duchess of Gloucester wore some gorgeous pieces of heirloom jewelry as she attended a special garden party at Buckingham Palace.

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The party celebrated the Not Forgotten Association, a national tri-service charity which provides entertainment, leisure and recreation for the serving wounded, injured or sick and for ex-service men and women with disabilities.

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Birgitte greeted veterans and those associated with the charity at the party. Here, she greets Rosie Thompson, the charity’s Head of Events.

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For the occasion, Birgitte wore her lovely silvery black pearls.

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She wore a classic single-stranded necklace featuring the pearls, as well as diamond and pearl earrings.

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Even more fascinating was the pendant she added to the necklace: a diamond and blue enamel lozenge, tipped with small pearls and featuring Queen Victoria’s imperial monogram. Birgitte has worn this jewel for years. The pendant could have arrived in her jewelry box in numerous ways — perhaps either as an inheritance from her mother-in-law, Princess Alice (via Queen Mary, most likely). It could also have been a legacy from Princess Marie Louise, who was the Duke’s godmother.