The Diamond Maple Leaf Brooch by Asprey
"This fantastic diamond brooch, made by Asprey, was a gift from King George VI to the Queen Mother ahead of their 1939 tour of Canada. The Queen Mother treasured the brooch, which is made to resemble a leaf of the Canadian Sugar Maple, and wore it throughout her life. The Queen inherited it from her mother in 2002. Both women have often loaned the brooch to other family members visiting Canada, and the Duchesses of Cornwall and Cambridge have made memorable recent appearances in the piece."
In the spring of 1939, just before the outbreak of World War II, King George VI and Queen Elizabeth made a state visit to Canada. He gave her the brooch, which was made by Asprey, to mark this state visit.
The brooch is made of diamonds set in platinum; Hugh Roberts describes it as being "in the form of a leaf of the Canadian Sugar Maple ... the national emblem of Canada, transparent-set with brilliants and baguettes."
Elizabeth wore it in public for the first time as they crossed the Atlantic in May 1939 on their way to Canada. It quickly became a staple in her brooch wardrobe.
The Queen inherited the brooch from her mother in March 2002. Today, she frequently wears the brooch both on trips to Canada and for events in Britain related to Canada.
From: www.thecourtjeweller.com/2016/05/the-diamond-maple-leaf-brooch.html?m=1