Queen Mary wears her wedding tiara and historic jewels as she begins tour of the Baltics

Queen Mary has chosen a very special piece of jewellery for a night of celebrations as she and King Frederik began a short tour of the Baltics.

The Danish royal and her husband arrived in Estonia on Tuesday where they had a full day of engagements before attending a state banquet and concert.

The King and Queen are on a two-day visit to the region as speculation of a larger tour of Australia increases, with an announcement expected in days.

Queen Mary, who will turn 54 next month, wore a dark blue silk gown by Prada featuring a glittering neckline to the evening reception.

The dress was first worn by Mary in 2015 to a New Year's Eve event at Christiansborg Palace in Copenhagen.

But it was the queen's headpiece which captured the most attention. She wore her wedding tiara, which has become one of Mary's favourite pieces of jewellery because of its sentimental value.

The King and Queen were guests of Estonia's president, Alar Karis and First Lady Sirje Karis, for the concert inside St. Nicholas Church.

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In his speech, King Frederik said some of his earliest memories of the Baltic country were formed by "Helga, my Estonian nanny, singing to me in her native language, reliving glimpses of her homeland, which she had fled as a child during World War II".

The state visit to Estonia, and Lithuania on Wednesday (Thursday in Australia), follows the King and Queen's visit to Latvia in October.

Denmark has strong historical ties to all three countries and established diplomatic relations for the first time in 1921. Denmark never recognised the Soviet annexation of the Baltic countries and, in August 1991, was among the first to re-establish diplomatic relations following their breakaway from the Soviet Union.

The King and Queen were officially welcomed to Estonia with a ceremony at Town Hall Square in Tallinn, before attending a wreath laying ceremony at the Monument to the War of Independence.

The glass monument is one of the city's most distinctive attractions and is located in Freedom Square.

Queen Mary was dressed in a blue outfit by her long-time Danish designer Lasse Spangenberg. She wore a matching blue silk and boucle headband by Katrin Cecilia Jacobsen.

Pinned to her dress was a diamond and sapphire brooch, known as the Flood Sapphire. It is part of The Danish Royal Property Trust, a collection of pieces reserved for the queen's use only. The trust was created by Frederik VIII and Queen Lovisa in 1910 to ensure important jewels would be passed down through the generations and not sold.

Queen Mary's predecessor, Queen Margrethe II, wore the brooch regularly throughout her 52-year-reign but this was the first time her daughter-in-law has been seen wearing the impressive jewel.

Mary's decision to wear blue for both the daytime and evening events was not a coincidence – the colour features on the Estonian flag and is another example of the royal's 'diplomatic dressing'.

The couple later met with the President and First Lady at the Presidential Palace before lighting a candle at the Memorial to the Victims of Communism. More than 75,000 citizens who were deported, imprisoned, or killed under the Soviet communist regime between 1940 and 1991.

The King and Queen then visited a girls' school, HK Unicorn Squad, with a focus on science and technology, where they joined opposing teams for a competition using homemade paper rockets.

Queen Mary was seen cheering with delight as her team's rocket hit its mark but ultimately the competition ended in a draw.

Tomorrow, the King and Queen will attend a ceremony in The Danish King's Garden, which according to legend, is where the Danish flag Dannebrog descended from the sky in 1219, making it possible for the Danish army to win the Battle of Lyndanisse.

They will then move onto Lithuania where the tour will end on Thursday night.

King Frederik and Queen Mary are expected to travel to Australia for an official state visit in the coming months.

Reports in Danish media suggest the King and Queen will arrive in March but no confirmation has been given by the Royal House.

Last week, Prime Minister Anthony Albanese appeared to confirm a visit would soon take place.

"Queen Mary is coming here," Albanese told KISS FM.

"She'll be here – I'm not sure that we've publicly released the dates, but it's quite exciting. Queen Mary and King Frederik."

In a statement to nine.com.au, the Danish Royal House said it was aware of the Prime Minister's remarks but declined to comment any further.

King Frederik and Queen Mary's last official joint tour was in 2013 when they came to celebrate the 40th anniversary of the Sydney Opera House, designed by Danish architect Jørn Utzon.

Queen Mary, when she was Crown Princess, last carried out an official duty in Australia on April 28, 2023, riding a bike through Sydney's CBD on a one-day solo visit focused on sustainability and green energy.

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