Duchess Kate wears ruby and diamond earrings she reportedly received as a wedding present to Commonwealth Day service

By Heather Cichowski, with files from Danielle Stacey

Duchess Kate was a vision in a crimson Catherine Walker coat with coordinating hat, heels and earrings at Commonwealth Day service at Westminster Abbey in London on March 9. Her sparkling earrings didn't get lost in the beauty of the other accessories she wore. They are a rarely seen piece from the mom of three's jewellery collection!

We first saw the duchess in the elegant double-breasted coat dress on Christmas Day in Sandringham in 2018. Kate completed this week's look with a Sally-Ann Provan floral hat and a pair of diamond and ruby earrings from Mouawad, a Geneva-based diamond house that has been crafting pieces since 1890.

Kate's elegant chignon updo ensured the diamond and ruby earrings were clearly visible. Photo: © Chris Jackson/Getty Images

The gorgeous accessories feature a rounded stud with long drop that extends down the neck to form a brilliant ruby flower.

MORE: Duchess Kate stuns in Jenny Packham at special gala dinner in support of patronage Place2Be

Kate and William appeared to be in high spirits at the Commonwealth Day service. Photo: © Yui Mok/PA Images via Getty Images

The special earrings reportedly match a set Kate wore way back in 2011, during her first few months as a royal. They're known as the Mouawad Ruby and Diamond Demi-Parure. On Dec. 19, 2011, the then-newlywed stepped out to The Sun Military Awards at the Imperial War Museum in the diamond and ruby necklace and bracelet and an Alexander McQueen gown, according to HELLO! UK. The luxurious necklace has the same ruby floral detail as the earrings.

For the gala, the duchess wore a different, shorter pair of earrings, so seeing them when she stepped out to Commonwealth Day service with Prince William and other members of the Royal Family was a delight!

Kate's style has always been dazzling. Photo: © John Stillwell- WPA Pool/Getty Images

The ruby and diamond jewels have even more significance because they are thought to be a wedding present from an unknown well-wisher.

The Duke and Duchess of Cambridge wed on April 29, 2011 at Westminster Abbey, and this year marks their ninth wedding anniversary. Seeing Kate out in the earrings at the same venue is a lovely tribute to her upcoming anniversary and the bond she shares with her husband.

The mom of three had a busy day on March 9! Following the Commonwealth Day service, Kate hosted a special reception for her patronage Place2Be that evening. She shone bright in a sapphire blue Jenny Packham dress featuring ornate embroidery across the bodice and sheer sleeves.

She accessorized with silver Jimmy Choo heels and blue floral earrings from Erdem.

Blue is definitely Kate's colour! Photo: © Chris Jackson - WPA Pool/Getty Images

The beautiful blue look was another time Kate reworked something from her closet! She previously wore the Jenny Packham gown to a charity gala in Mumbai during royal visit to India and Bhutan with William in 2016.

The elegant gown looked as good this time as it did on the tour!

Don't miss a beat with HELLO! Canada's Daily Hits newsletter, your daily dose of royal and celebrity news, fashion, weddings and more. CLICK HERE to sign up for free!