One notable occasion was a visit to the United States in 1951 – the Princess wore the clips when she arrived at the airport in Washington.
One was pinned on the collar of her jacket, while the other was pinned to her hat.
Interestingly, the brooches were the last jewels Princess Elizabeth was pictured wearing in public before her sudden accession to the throne in 1952, according to the Court Jeweller.
She and the Duke of Edinburgh, whom she had married in 1947, were in Kenya at the start of a planned Commonwealth tour.
source: express.co.uk