Sapphire Specialist Mini Course
The Logan Sapphire
One of the world’s most recognizable sapphires is the Logan Blue Sapphire. On display at the Smithsonian since 1971, this gem weighs 422.99 cts. It’s the largest set gem in the National Gem Collection and the second largest faceted sapphire in the world. With a pure medium-blue color and excellent clarity, its quality is readily apparent to all visitors.
The Logan Sapphire originated in Sri Lanka’s Ratnapura gem mining district, likely in the 1900s. Col. M. Robert Guggenheim purchased the sapphire as a gift for his wife, Rebecca Pollard Guggenheim, in 1952. After his death in 1959, she donated the gem to the Smithsonian but kept it in her possession until 1971. Upon remarrying in 1962, the gem acquired her new surname, Logan.
Kate Middleton’s Sapphire Engagement Ring
Heirloom engagement rings are a popular way for young couples to celebrate the old and the new. But few engagement rings are as high-profile and trend-setting as Kate Middleton’s.
The ring was originally Princess Diana’s sapphire engagement ring. After her untimely death, her sons were each encouraged to keep a memento. Prince William chose a gold Cartier watch, while Prince Harry picked the engagement ring. When William…
A geologist, environmental engineer and Caltech graduate, Addison’s interest in the mesmerizing and beautiful results of earth’s geological processes began in her elementary school’s environmental club. When she isn’t writing about gems and minerals, Addison spends winters studying ancient climates in Iceland and summers hiking the Colorado Rockies.
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