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