do you know which brooch Queen Elizabeth II is wearing on the picture below?
Is it the pearl and diamond brooch of the Duchess of Cambridge (Queen Mary's grand-mother), which was inherited by Princess Marie-Adelaide, Duchess of Teck in 1889, by Queen Mary in 1897 and by Queen Elizabeth II in 1953? Then the brooch would be worn, here, without the pearl drop (and with a tricking greyish overtone, which might just be an effect of the lighting)?
Or do you think it is another brooch? For example, we know from Leslie Field's book The Queen's Jewels that Queen Victoria's Jubilee necklace was accompanied by a round pearl and diamond cluster brooch, here worn by Queen Victoria: