Marchione's interest in
Filippo Mazzei began in 1974 bicentennial. Filippo Mazzei (1730–1816) was an Italian physician, philosopher, diplomat, and author, who moved to
Virginia, fought in the American Revolution, and became a lifelong personal friend of
Thomas Jefferson. The author of seven volumes on Mazzei, Marchione donated approximately 2,500 printed and published artifacts, works of art and decorative objects of Philip Mazzei to the Thomas Jefferson Foundation. Foundation librarian Jack Robertson stated, "The collection compiled by Sister Margherita includes not only facsimiles of all of Mazzei's correspondence, but relatively obscure publications on the role of Italians in American history." She launched an ultimately successful campaign to get the
United States Postal Service (USPS) to designate a stamp to commemorate Mazzei in the form of a 40 cent airmail stamp in 1980 to commemorate Mazzei's 250th birthday. ==Pius XII==