The dowager duchess wore the smaller of the Devonshire tiaras to the Queen's Coronation in 1953. She was likely the only duchess in attendance wearing the family's second-best tiara. This was due to her mother-in-law Mary having a highly visible role during the ceremony - Mistress of the Robes.
This tiara was worn by the current duchess as a bride.
Her Grace also wore the tiara as a necklace.
Some of the motifs were also worn as brooches.
I must run for now, but I'll have more later this evening.