The Queen chose a sparkling diamond brooch with an 18.8-carat heart-shaped stone at its centre for her husband’s official 99th birthday photograph.
The monarch picked the Cullinan V – one of her favourite pieces of jewellery – for the portrait with her husband of more than 70 years.
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She has worn it many times over the decades including to the wedding of her granddaughter Princess Eugenie, at London Fashion Week, and for State Openings of Parliament, garden parties, investitures and audiences.
The Cullinan V originally belonged to the monarch’s grandmother, Queen Mary, and was worn as part of the suite of jewellery made for the Delhi Durbar in 1911.
It is one of a number of stones cut from the famous 3,106-carat Cullinan – the largest diamond ever found.
Mined in South Africa, the original Cullinan stone was given to King Edward VII in 1907 by the government of the Transvaal – a symbolic gesture intended to heal the rift between Britain and South Africa following the Boer War.
Parts of it were later set in the Crown Jewels – in the Sovereign’s Sceptre and the Imperial State Crown.
The royal family refer to some of the other pieces from the original diamond – the Cullinan III – a pear shaped 94.4-carat drop – and Cullinan IV – a cushion-shaped 63.6-carat diamond – mounted together as a brooch – as ‘Granny’s chips’.
The Queen inherited the brooches on Queen Mary’s death in 1953.
The Duke of the Edinburgh has seen a lot in his long life – having served in the Second World War, he was awarded the Greek War Cross of Valour for his participation in the Battle of Crete.
He was also mentioned in dispatches for his service during the Battle of Cape Matapan, where he saved his ship from a night bomber attack by spotting the enemy vessel.
Philip began his naval career at the Britannia Royal Naval College, in Dartmouth, in 1939, where he won two prizes for being the best cadet.
It was around this time that he also first began corresponding with Queen Elizabeth II, who took a tour of the college with her sister Princess Margaret the same year.
He then joined the battleship HMS Ramillies in 1940 as a midshipman and spent six months in the Indian Ocean.
Philip’s actions saw him rise through the ranks, and at 21 he became one of the youngest officers in the Royal Navy to be made First Lieutenant and second-in-command of a ship in 1942.
The Queen and Prince Philip had first met in 1934 at the wedding of Princess Marina of Greece and Denmark to Prince George, Duke of Kent.
The Queen, however, was just eight while the Duke was 14 and had been essentially abandoned by his family and was at boarding school at Gordonstoun.
Five years later their paths would cross again at Dartmouth Naval College as Britain was on the brink of war.
With a shock of bright Scandinavian blond hair, tall and athletic, Philip was attractive to many.
He was described as ‘very amusing, full of life and energy and a tease’.
By contrast, the young Princess Elizabeth was a serious and shy child who was very much protected from life by her father King George IV.
Prince Philip recalled telling Elizabeth that she was so shy he couldn’t get a word out of her during the meeting.
In turn, her memory of the day was that he wolfed down a plate of shrimps like he had never eaten before in his life.
It was certainly a case of opposites attract and after the war, in 1946, the Prince asked King George for his eldest daughter’s hand in marriage.
He was initially refused, despite the fact the King liked the Greek-born young Naval officer.
He was unlike the aristocrat Princess Elizabeth would have been expected to marry in that while he had titles, he had no money and no estate.
But more than that, the King was fearful that Prince Philip wasn’t British and didn’t belong to the Church of England.
The Queen Mother wrote to her soon-to-be son-in-law asking for his assurance that he would ‘cherish’ her daughter.
He replied he had ‘fallen in love completely and unreservedly’ and promised that his ambition was to make them a team that could take on the world.
The engagement was announced on July 9, 1947 after the Queen had turned 21.
Philip proposed to Elizabeth with a ring consisting of a centre stone surrounded by 10 smaller pave diamonds taken from a tiara that belonged to his mother Princess Alice.
The wedding took place four months after the engagement on November 20 at Westminster Abbey and was watched by 200 million people worldwide.
Philip continued to serve in the Navy until 1951, when he returned to the UK with the Elizabeth, due to the king’s failing health.
He was then forced to end his military career when his wife became Queen.
After her coronation, he became the first layman to pay homage to the monarch, swearing to be her ‘liege man of life and limb’.
In 2011, the Queen made him Lord High Admiral, titular head of the Royal Navy, as he turned 90.
The Duke of Edinburgh is no stranger to controversy, even in recent years – last year he made the headlines after flipping his Land Rover while pulling out of a driveway and hitting another car near the Sandringham Estate.
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