Queen Camilla brought one of the more mysterious jewels in her person collection back into rotation on Wednesday, pairing her moonstone and diamond brooch with a mostly monochrome Anna Valentine look for the Royal Osteoporosis Society at Clarence House in London.

Queen Camilla

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The queen rewore an icy blue Anna Valentine dress designed in her signature silhouette. The dress was crafted in a muted gray-blue tone with three-quarter length sleeves and a midi hemline. Exposed seams ran down the front of the dress, which featured a slightly pleated skirt.

Queen Camilla accessorized with her oft-worn Van Cleef & Arpels bracelets, a pair of pearl and diamond earrings and the moonstone and diamond brooch.