A look at the most show-stopping diamonds worn by Kate by Hanna Fillingham / 14 November 2017 They say diamonds are a girl's best friend, and that certainly seems to be the case for the Duchess of Cambridge. Over the years, Kate has been seen dazzling in an array of sparkly accessories, many of which have sentimental meaning behind them. Grant Mobley, a gemologist and Director at Pluczenik, one of the world’s leading diamantaires, has given HELLO! Online the low-down on Kate's most spectacular pieces. "The size, quality, and number of the diamonds in these exquisite pieces make them incredibly valuable – and their history and sentimental significance make them priceless," he said. "One of the amazing parts of owning fine jewellery is its ability to stand the test of time and be passed down while gaining in value. In the diamond industry, we’re seeing news about manmade diamonds which take two weeks to produce in a factory, and while their look and composition are similar to real diamonds, their lack of rarity and authenticity renders them literally valueless. It’s unimaginable that the Duchess of Cambridge, or any member of the Royal Family, would wear a factory-grown diamond. Why opt for something artificial and worthless over a real diamond that is rich in history and inherent value – and a precious heirloom that The Duchess of Cambridge can pass on to her children?" Take a look through the most iconic diamond pieces Kate has worn, from the Lover's Knot tiara to the Queen's diamond-encrusted maple leaf brooch… Read more about: Kate Middleton Kate style Fashion News Kate looked sensational on her wedding day to Prince William in 2011, and dazzled in diamonds - including the Cartier Halo Tiara. Grant said of her magnificent headwear: "This tiara has a total of nearly 1,000 diamonds and was originally purchased from Cartier in 1936 as an anniversary gift from King George VI to his wife, Queen Elizabeth I and then was re-gifted to Queen Elizabeth II on her 18th birthday." While at the black tie gala at the Met in New York back in 2014, Kate co-ordinated her emerald Jenny Packham gown with a stunning diamond and emerald bracelet and matching earrings. Grant said of her choice: "This bracelet is made of two rows of diamonds which are connected to a centre stone consisting of a large emerald set in a square-cut diamond setting. The diamonds paired with the emerald stone makes this a very striking piece." Grant listed Kate's diamond and sapphire fringe earrings - which once belonged to the Queen Mother - as one of her most memorable diamond accessories. "The diamond and sapphire fringe earrings that Kate wore to the 2015 Women in Hedge Funds Dinner are among the many heirloom Royal jewels that now belong to The Duchess of Cambridge," he said. "These once belonged to the Queen Mother, who like Princess Diana was a big fan of sapphires." In 2011, Kate stepped out to attend The Sun Military Awards with husband Prince William and brother-in-law Prince Harry. The Duchess wore a gorgeous diamond and ruby necklace to the emotional ceremony, which Grant also noted as one of her most memorable pieces. "This necklace is made up of dropdown diamond chains suspended from the diamond collar which is very a similar style to the necklace that was gifted to the Queen by King Khalid of Saudi Arabia," he said. Kate's enegagement ring is estimated to be worth £300,000, but is now priceless, says Grant, who names it as the most iconic piece of her diamond jewellery. "It goes without saying that the most iconic piece of diamond jewelry owned by The Duchess of Cambridge is her House of Garrard-designed engagement ring, featuring an oval 12-carat Ceylon sapphire surrounded by 14 solitaire diamonds set in white gold," he said. "This statement piece cost £28,500 ($37,604) in 1981 and now has an estimated value of £300,000 ($395,830), but really due to its history and its ownership it is priceless." Grant named Princess Diana's pearl and diamond bracelet as another key diamond piece worn by Kate, and The Duchess was pictured with it on a number of time during the Royal Tour of Poland and Germany earlier this year. "The bracelet is easily recognizable with its unique circular diamond spacers separating the three strands of pearls on the wrist. This is another piece that was made from a combination of both diamonds and pearls, of which Kate seems to be a fan," Grant said. The Lover's Knot tiara, which Kate has been pictured wearing on several occasions - most recently at a state banquet at Buckingham Palace to welcome Queen Letizia and King Felipe of Spain. It was a gift given from the Queen to Princess Diana on her wedding day in 1981, and created by jewellers Garrard in 1914 for Queen Mary. Grant describes the iconic tiara as "another stample diamond piece." He observed: "Although, Kate doesn’t appear to be a big fan of tiaras, she has been pictured wearing this particular one numerous times. It may be one of her favorites because it’s made from a combination of diamonds and pearls, and as we know from her jewelry choices, Kate is a big fan of both. Interestingly, this was made from diamonds and pearls that the royal family already owned so it’s definitely a piece that is incredibly precious and rich in history." Kate turned heads when she stepped out wearing the Queen's Nizam of Hyderbad necklace to the National Portrait Gallery in 2014, and Grant describes the pieces as "spectacular." He said: "The Nizam of Hyderabad necklace is also one of the most spectacular pieces Kate has worn, featuring a staggering 38 diamonds, while its centre boasts 13 emerald cut diamonds and a pear-shaped drop. As you can imagine, thanks to its diamond composition, it’s incredibly valuable and precious." Along with Kate's Halo tiara, her wedding earrings were also spectacular. Grant described the sentimental design - which was a custom-made from the Duchess' mum and dad - as "elegant and timeless." What's more, the one-off pair featured a diamon stylised acorn and oak leaf - both part of the Middleton family’s coat of arms. The diamond-encrusted maple leaf brooch that The Duchess of Cambridge wore during the 2011 Canadian tour is pretty special. Grant said of the royal heirloom: "This piece was borrowed from the Queen’s jewellery collection and is one of the most iconic and recognisable brooches that she owns. First worn by the Queen’s mother on her first visit to Canada in 1939, and then by the Queen in 1951, it’s a stunning diamond composition with history and meaning to the family, and their Canadian subjects, which makes it an enduring favorite."