It was very fashionable, in the 1920s and 1930s, to have bejewelled twin clips.
One of the most famous of these pair of earrings is of course Queen Elizabeth II's Boucheron Aquamarine Clips (an 18th-birthday present by the Queen's parents in 1944).
She has also worn two of Queen Victoria's Wheat-Ear Brooches (here in Oman in 2010):
I think she has never worn two of Queen Victoria's Diamond Bow Brooches.
--Previous Message-- : : Perhaps a new thread is in order here, for : royal ladies wearing their brooches in twos, : paired or not. : : To start with Princess Marina, Duchess of : Kent wearing two varieties of her paired : sapphire brooches (the second pair is : different). : : : : :