Members of the British royal family wearing diamonds, the official gemstone of April

When one thinks of royalty, diamonds often come to mind.

Some of the most spectacular diamond pieces are owned by royal families around the world, used for the most formal of events. Diamonds are also the official birthstone for April.

These decadent jewels are regularly worn by royal women including Catherine, Princess of Wales, Camilla, Queen Consort and Meghan, Duchess of Sussex.

It was also a favoured gemstone for the late Queen Elizabeth II and Diana, Princess of Wales.?

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Kate has been a fond wearer of the April gemstone, often seen appearing at royal events donning the Nizam of Hyderabad necklace, which? is a stunning piece.

The necklace? is usually reserved for major royal events, and while Kate recovers from her cancer diagnosis, it's unlikely we will see her don these jewels any time soon.

The Nizam of Hyderabad was one of the world's richest men and showed his wealth by gifting Princess Elizabeth a diamond necklace and tiara for her wedding in 1947, both made by Cartier.

The tiara featured an English rose design, with three detachable brooches but was dismantled to create the Burmese Rubies tiara.

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However, the necklace remains and was occasionally by Queen Elizabeth II during her reign.

It was seen on Kate, the Princess of Wales, at the Diplomatic Corps reception inside Buckingham Palace on December 11, 2019.

The princess wore the necklace with Queen Mary's Lover's Knot tiara.

The Duchess of Sussex wore Queen Mary's Bandeau tiara for her royal wedding to Prince Harry on May 19, 2018.

The tiara was created in 1932 to match a brooch which now sits in the centre of the piece.

The platinum and diamond brooch, crafted from 10 brilliant diamonds, was given to Queen Mary in 1893 as a wedding gift.

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Kate also chose the Cartier Halo tiara for her royal wedding to Prince William on April 29, 2011, at Westminster Abbey.

The piece was borrowed from the Queen's collection.

It was originally made for the Queen Mother in 1936, a commission from her husband King George VI.

The Cartier Halo tiara is set with 739 brilliant-cut diamonds and 149 baton-cut diamonds.

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Lady Diana chose a family heirloom for her wedding to Prince Charles on July 29, 1981.

The Spencer tiara has been in the aristocratic family for nearly a century and is made from several separate pieces belonging to Diana's female relatives.

In the 1930s royal jewellers Garrard & Co. crafted the various elements into the tiara we know today.

Diana wore the piece throughout her time as Princess of Wales but the tiara remains part of the Spencer family collection, owned by her brother Charles Spencer, the 9th Earl Spencer.

Camilla, Queen Consort, has had access to some of the royal family's grandest diamonds since marrying into the British monarchy.

She has been seen wearign the Delhi Durbar tiara in the past.?

This tiara is part of an extraordinary set of jewels made for Queen Mary in 1911 for King George V's coronation and named for the Delhi Durbar, the Indian celebration to mark the beginning of his reign.

It was crafted by Garrard and originally featured emeralds, which were later removed and used in the Grand Duchess Vladimir tiara.

It is one of three tiaras worn by Camilla when she was Duchess of Cornwall, loaned from Queen Elizabeth II.

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At the coronation in May 2023, Camilla wore a crown first made for Queen Mary in 1911.

The crown was remodelled and reset with three of the ?biggest and most expensive diamonds previously worn by Queen Elizabeth II as brooches ¨C the Cullinan III, IV and V diamonds.

The Cullinan diamonds have been set into Queen Mary's Crown on previous occasions.

Queen Elizabeth II often wore the ?III and IV diamonds as a single brooch.

Made by Carrington & Co in 1911, the brooch features two large stones cut from the Cullinan diamond ¡ª the world's largest diamond ever found, which was cut into many other smaller, yet still very impressive, stones.

Two of the biggest, the Cullinan I and II, are now set in the Sovereign's Sceptre and the Imperial State Crown.

The two stones that form this brooch ¡ª the Cullinan III and IV ¡ª weigh 94.4 and 63.6 carats.

They were famously called 'Granny's Chips' during Queen Elizbeth's visit to The Netherlands in 1958, because they are so-called off-cuts from the original.

The two stones are a pear-shaped diamond and a square-cut brilliant.