Samuel Gibson Frantz was born on March 15, 1897 in Duluth, Minnesota to Mary Katherine (Gibson) Frantz, wife of Alfred Jacob Frantz. Following his father's death in 1905 the family moved to Edinburgh, Scotland, and Frantz entered the Edinburgh Academy where he consistently achieved grades near the top of his class, and was outstanding in Latin and Mathematics.

The family returned to the United States in 1910 and resided in Princeton, New Jersey. Frantz entered The Lawrenceville School nearby, from which he graduated in 1913. He entered Princeton University as a member of the class of 1918 at the age of 16, but left shortly after the beginning of World War I to serve as an ambulance driver with the American Field Service in France. He also served in the U.S. Air Service (Aero) of the Army as a balloonist and aerial observer in France. Frantz was discharged as a second lieutenant at the end of the war.

Reentering Princeton, Frantz graduated in 1919 with a degree in civil engineering and membership in the honorary societies Phi Beta Kappa and Sigma Xi.

He married Sarah Wistar Morton in 1921 and during the following decade, Frantz did several kinds of engineering work, including some municipal civil engineering as an independent contractor. In 1923 he obtained the Master of Science degree in Physics from Princeton University. Beginning in the same year he studied at the Ecole Supérieure d' Electricité of the Sorbonne in France. By 1932 he was well advanced in the field that was to be his life's work. He co-authored a paper that year which was delivered at a meeting of the American Institute of Mining and Metallurgical Engineers. It described the induced roll separator invented in 1926 by Fred R. Johnson of the Exolon Co., which at the time was considered a major step forward in the technology. It expressed the view that . . . research both in the design of machines and in their applications will continue in the next five years as rapidly as it has in the last five years and make the magnetic method one of the most important tools in ore dressing.

Frantz founded S.G. Frantz Company in 1935 to manufacture products embodying his inventions, and started operations in a loft in New York City. The patent in which he disclosed the principles of design governing sensitive separation according to susceptibility (US #2,056,426) was issued to him the following year. In the ensuing years he received a total of four more patents:

1937 – for a separator consisting of an iron jacketed solenoid with a filamentary matrix in the bore of the solenoid, principles of design which today govern separators for magnetic filtration of materials (US #2,074,085)

1943 – for a separator for magnetic filtration of dry materials (US #2,331,769)

1950 – for a separator for magnetic filtration of wet materials with oppositely polarized permanent magnets above and below a filamentary matrix (US #2,508,666)

1965 – for a device employing oppositely polarized permanent magnets for magnetizing a matrix that performs a straining function as well as magnetic separation (US #3,221,882)

Except for a hiatus from 1943 to 1944 when he served as Chief of the Operations Analysis Section of the Ninth Air Force in Benghazi, Libya (where he, with his group, developed a manual which became the official training booklet for aerial machine gunnery throughout the Air Force) and later in Tunisia and Bari, Italy with the XII Bomber Command (which became the Fifteenth Air Force), Frantz devoted the rest of his life to the processes he was inventing. In 1950 he moved the base of operations to Lawrenceville, New Jersey, where the company still manufactures separators of superior quality and design. He died in 1971.