Ishbel Hamilton-Gordon, Marchioness of Aberdeen and Temair wears a diamond festoon tiara topped with sapphire clusters in a photographic portrait, ca. 1899; I’m not sure what happened to the jewels following Ishbel’s death in 1939

Princess Louise, Marchioness of Lorne (later Duchess of Argyll) wears her diamond and emerald tiara in a portrait, ca. 1870s; the tiara, which was a wedding gift from Louise’s parents-in-law, was likely among the jewels she bequeathed to the Duke and Duchess of Kent in 1939