Question: George Shirley Switzer started the Smithsonian Institution's famed National Gem and Mineral Collection by acquiring what jewel weighs 45.52 carats?

Context articles: George Switzer (mineralogist)
Hope Diamond
List of aircraft in the Smithsonian Institution
George-ericksenite
Smithsonian Folkways
Yogo sapphire
Smithsonian Libraries
Dom Pedro aquamarine
Galaxy opal
Eugene Jarosewich

George Shirley Switzer (June 11, 1915 – March 23, 2008) was an American mineralogist who is credited with starting the Smithsonian Institution's famed National Gem and Mineral Collection by acquiring the Hope Diamond for the museum in 1958.
 Switzer made the arrangements when renowned New York City jeweler Harry Winston decided to donate the Hope Diamond to the Smithsonian.
The Hope Diamond is one of the most famous jewels in the world, with ownership records dating back almost four centuries.
 Its much-admired rare blue color is due to trace amounts of boron atoms.
 Weighing 45.52 carats, its exceptional size has revealed new findings about the formation of gemstones.
The List of aircraft in the Smithsonian Institution includes aircraft exhibited in the Smithsonian Institution's National Air and Space Museum, Steven F. Udvar-Hazy Center, and the Paul E. Garber Preservation, Restoration, and Storage Facility.
 The Smithsonian Institution's collection of aircraft and spacecraft is the largest on display in the world.
George-ericksenite is a mineral with the chemical formula NaCaMg(IO)(CrO)(HO).
 It is vitreous, pale yellow to bright lemon yellow, brittle, and features a prismatic to acicular crystal habit along [001] and somewhat flattened crystal habit on {110}.
 It was first encountered in 1984 at the Pinch Mineralogical Museum.
 One specimen of dietzeite from Oficina Chacabuco, Chile had bright lemon-yellow micronodules on it.
 These crystals produced an X-ray powder diffraction pattern that did not match any XRD data listed for inorganic compounds.
 The X-ray diffraction pattern and powder mount were set aside until 1994.
 By then, the entire mineral collection from the Pinch Mineralogical Museum had been purchased by the Canadian Museum of Nature.
 The specimen was then retrieved and studied further.
 This study was successful and the new mineral george-ericksenite was discovered.
 The mineral was named for George E. Ericksen who was a research economic geologist with the U.S. Geological Survey for fifty years.
 The mineral and name have been approved by Commission on New Minerals and Mineral Names (IMA).
 The specimen, polished thin section, and the actual crystal used for the structure determination are kept in the Display Series of the National Mineral Collection of Canada at the Canadian Museum of Nature, Ottawa, Ontario.
Smithsonian Folkways is the nonprofit record label of the Smithsonian Institution.
 It is a part of the Smithsonian's Smithsonian Center for Folklife and Cultural Heritage, located at Capital Gallery in downtown Washington, D.C. The label was founded in 1987 after the family of Moses Asch, founder of Folkways Records, donated the entire Folkways Records label to the Smithsonian.
 The donation was made on the condition that the Institution continue Asch's policy that each of the more than 2,000 albums of Folkways Records remain in print forever, regardless of sales.
 Since then, the label has expanded on Asch’s vision of documenting the sounds of the world, adding six other record labels to the collection, as well as releasing over 300 new recordings.
 Some well-known artists have contributed to the Smithsonian Folkways collection, including Pete Seeger, Ella Jenkins, Woody Guthrie, and Lead Belly.
 Famous songs include "This Land Is Your Land", "Goodnight, Irene", and "Midnight Special."
 Due to the unique nature of its recordings, which include an extensive collection of traditional American music, children's music, and international music, Smithsonian Folkways has become an important collection to the musical community, especially to ethnomusicologists, who utilize the recordings of "people's music" from all over the world.
Yogo sapphires are a variety of corundum found only in Yogo Gulch, part of the Little Belt Mountains in Judith Basin County, Montana, United States, on land once inhabited by the Piegan Blackfeet people.
 Yogos are typically cornflower blue, a result of trace amounts of iron and titanium.
 They have high uniform clarity and maintain their brilliance under artificial light.
 Because Yogo sapphires occur within a vertically dipping resistive igneous dike, mining efforts have been sporadic and rarely profitable.
 It is estimated that at least 28 million carats (5.6 t ) of Yogos are still in the ground.
 Jewelry containing Yogos was given to First Ladies Florence Harding and Bess Truman; in addition, many gems were sold in Europe, though promoters' claims that Yogos are in the crown jewels of England or the engagement ring of Princess Diana are dubious.
 Today, several Yogo sapphires are part of the Smithsonian Institution's gem collection.
Smithsonian Libraries (SIL), formerly known as Smithsonian Institution Libraries, is a library system comprising 20 branch libraries serving the various Smithsonian Institution museums and research centers, as well as central support services which include a Book Conservation Laboratory and an Imaging Center.
 The Libraries serve Smithsonian Institution staff as well as the scholarly community and general public with information and reference support.
 Its collections number over 1.5 million volumes including 40,000 rare books and 2,000 manuscripts.
 The Libraries also holds the United States' largest trade literature collection, which includes over 300,000 commercial catalogs dating from the early nineteenth century and representing more than 30,000 companies.
The Dom Pedro aquamarine is the world's largest cut aquamarine gem.
 It was cut from a crystal originally weighing approximately 100 lb and measuring more than 3 ft in length.
 The stone was mined in Pedra Azul, in the state of Minas Gerais in Brazil around 1980, and named after the Brazilian emperors Pedro I and Pedro II.
 The blue-green gemstone was cut by Bernd Munsteiner into an obelisk form weighing 10,363 carats.
 The finished dimensions measure 14 in tall by 4 in wide.
 The jewel was donated to the Smithsonian Institution by Jane Mitchell and Jeffery Bland.
 It is housed in the National Museum of Natural History's Janet Annenberg Hooker Hall of Geology.
The Galaxy is the world's largest polished opal, certified by the Guinness Book of World Records in 1992.
 It was found at the Boi Morto Mine in north eastern Brazil in 1976.
 It is today part of a private collection.
 The finished opal weighs approximately 3,749 carats, or 0.75 kg.
 It was carved from a grapefruit-sized piece of rough stone weighing 5,205 carats by Scott Cooley into a shape resembling a child's head.
 The weight of the finished stone was beyond the capacity of any gem measuring scale at the Gemological Institute of America and an approximation of its weight in carats had to be determined using a postal scale.
 The stone measures 14.0 x 10.2 x 4.1 cm (5-1/2 x 4 x 1-5/8 in).
Eugene (Gene) Jarosewich (1926–2007) was a chemist in the Department of Mineral Sciences at the Smithsonian Institution.
 Gene was known worldwide for his wet chemical analyses of meteorites.
 Working with specimens from the National Mineral Collection, Gene and his co-workers also developed a set of commonly used standards for electron microprobe analyses.