The Queen’s Cullinan III and IV brooch is Her Majesty’s most expensive brooch according to the experts, costing roughly £50million.

Claire Adler, founder of Claire Adler Luxury PR which specialises in working with jewellery clients, spoke exclusively to Express.co.uk about the Queen’s brooch.

She said: “A mixture of tradition and style, Her Royal Majesty has worn a vast array of brooches over the years.

“Through each choice, this distinct accessory is meticulously paired to suit each of the Queen’s royal engagements, and her choice in brooch conveys meaning through its historical context and provenance.

“For example, the Cullinan III and IV brooch, which is the most valuable in the world, let alone in the Queen’s collection, has been worn on average once every decade,” the expert said.

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