The uncomfortable truth behind the Imperial Crown and its glittering jewels

Images of the Imperial State Crown have been broadcast around the world in recent days as one of the UK's principal crowns took centre stage during the funeral of Queen Elizabeth.

While many describe it as a symbol of the monarchy and Britishness, for some it is a symbol of something else: its namesake, imperialism.

Yahoo News UK explores this priceless crown's nearly 1,000 years of history and why it is problematic for so many people.

Imperial by name... Imperial crowns are used for the coronation of emperors, and the British Imperial State Crown is inextricably linked with the British Empire. The king or queen of the day was the de facto head of the Empire and the Imperial State Crown arguably the most iconic ceremonial object associated with the monarch.

What's it for? The current Imperial State Crown was made for King George VI in 1937 and replaced the one created for Queen Victoria in 1838. It is worn by the monarch as they leave Westminster Abbey following the coronation. The monarch also holds a sceptre and orb with all three together symbolising his or her power and governance. The crown is also worn during state openings of parliament. If a monarch is unable to attend a state opening, an heir may be sent in their place with the crown placed on a cushion.

It's very glittery Indeed. The crown consists of 2,868 diamonds, 17 sapphires, 11 emeralds, 269 pearls, and four rubies. The crown, which has a gold frame, contains several famous jewels - including the Black Prince's Ruby, the Stuart Sapphire, and the Cullinan II diamond, the latter of which is also known as the Second Star of Africa. While it is regarded as priceless, some reports have placed its worth as anything up to £5bn. But who knows?

Jewel #1 The Black Prince's ruby is one of the oldest constituent parts of the crown and dates back to 14th century. It is believed the stone – which is not actually a ruby, but a spinel – originally came from a mine in what is now Afghanistan and Tajikistan. It has been in the possession of English rulers since Edward the Black Prince, the eldest son of King Edward III, acquired it for helping suppress a revolt in modern-day Spain.

Jewel #2 St Edward's sapphire is older than any other gemstone in the crown, and is believed to be from the coronation ring of Edward the Confessor in 1042. It was added to the crown by Queen Victoria and is believed to have originally come from Asia.

Jewel #3 Cullinan II – also known as the Second Star of Africa – is mounted in the middle of the crown. It was taken from a mine in British-occupied South Africa in 1905, and is named after the mine's owner, Thomas Cullinan. Cullinan II was cut from the Cullinan diamond – the largest diamond ever recorded – when it was separated into nine major stones and 96 smaller ones, several of which are in the Crown jewels.

Why the controversy? The Cullinan diamonds in particular are controversial because they were taken from South Africa during the British Empire's occupation. The British committed a long list of atrocities in the region, most notably forcibly placing Boer and black African men, women and children into concentration camps as part of the infamous "scorched-earth" policy. The country's mineral riches were important to the British economy, so colonial forces sought to protect their access to them.

Why does this matter now? Activists around the world have called on the the Royal Family to repatriate stolen jewels, such as Cullinan II. South African MP Vuyo Zungula said following the Queen's death that his country must "demand the return of all gold and diamonds stolen by Britain". University of South Africa professor of African politics Everisto Benyera said the private mining companies and the Transvaal and Union of South Africa governments in the 19th and 20th century were "part of a larger network of coloniality". Many in India have been similarly vocal about the return of the Koh-i-noor diamond, which can be found in the front of the Queen Mary's Crown.

So what's stopping them? The counter-argument is that objects looted during colonialism and British imperialism should remain in the UK as they are part of its history. Others dismiss the seriousness of modern-day concerns by pointing out that other European countries behaved in a similar fashion at the time. These critics argue it is in the past, and society should move on.

What have the royals said? In the eyes of many, not enough. Elizabeth II never publicly acknowledged the debate surrounding the issue of stolen jewels. Instead, she focused on promoting the Commonwealth following the collapse of the British Empire. Her successor, King Charles, expressed his "personal sorrow" over historical slavery and said, in June this year, that "this is a conversation whose time has come". Many will be wondering if these words will ever be matched by deeds.