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Zay Jeffries

Death: May 21, 1965 (77)
Immediate Family:

Son of Johnston Jeffries and Florence Jeffries

Managed by: Private User
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Immediate Family

About Zay Jeffries

Zay Jeffries (April 22, 1888 – May 21, 1965) was an American mining engineer, metallurgist, consulting engineer and recipient of the 1946 John Fritz Medal.


Jeffries was born in Willow Lake, South Dakota as one of the nine children of Johnston Jeffries and Florence (Sutton) Jeffries. He obtained his BSc in mining engineering at the South Dakota School of Mines and Technology in 1910. Three years later, he also obtained his MSc in metallurgical engineering from the same school, and in 1918 Harvard University awarded him his Doctor of Science degree.

After his graduation in 1910 he started as an assayer for the Custer mining company in South Dakota, and later that year he accepted an appointment as an instructor at Case Western Reserve University in Cleveland. In 1916 he was promoted to appointed assistant.

In 1914 he also started as a consulting engineer in the Cleveland-area. Later he consulted for metallurgy laboratories, and at the University of Chicago; he participated in the Manhattan Project.

Jeffries was elected a member of the National Academy of Sciences in 1939. In 1946 he was awarded the John Fritz Medal.

In 1950, Jeffries became the Leonard Case Professor on Educational Policy at Case Western.

Jeffries was also a vice president of General Electric: as such, he and other officers were prosecuted in 1948 for violating federal law; that same year, he also received the Medal for Merit. In his later years, Jeffries retired to Pittsfield, Massachusetts, where he died of cancer in May 1965, survived by his wife and daughter.


On October 10, 2019, President Donald Trump issued a full pardon to Jeffries for a conviction for engaging in anti-competitive practices in violation of the Sherman Antitrust Act of 1890, for which Jeffries had been convicted in 1948, and assessed a $2,500 fine (equivalent to $27,000 in 2020) with no jail time.

Associated Press Announcement on Oct 11, 2019:

WASHINGTON (AP) — President Donald Trump is awarding a posthumous pardon to a leading metal scientist whose work helped secure an Allied victory in World War II.

The White House announced on Thursday that Trump was granting clemency to Zay Jeffries, who grew up in Fort Pierre, South Dakota. He helped develop artillery shells capable of piercing the armor of German tanks and also consulted on the Manhattan Project to build the atomic bomb.

Jeffries was indicted in 1941 on antitrust charges related to his employment, but top defense officials asked for his prosecution to be delayed until after the war. He was convicted and fined $2,500 in 1948 — the same year that President Harry S. Truman awarded him the Presidential Medal for Merit. He died in 1965.

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Zay Jeffries's Timeline

April 22, 1888
May 21, 1965
Age 77