, Australia, ca 1975. In 1950 Dunn was a key member of the research and development team at
E.I. DuPont de Nemours in
Wilmington, Delaware which developed an improved process for the production of high-purity
titanium dioxide for use as a paint pigment. He filed his first sole-inventor U.S. patent in 1954. He remained with the firm for 19 years during which time this process grew to become the dominant technology worldwide. In 1968 Dunn left DuPont to form his own contract research and development firm in Delaware and
Sydney, Australia. He worked closely for several years with a major Australian mining house,
Peko-Wallsend, to develop a technology to produce a low-cost titanium process feedstock. Thereafter, Dunn returned to
South Dakota and for the next three decades made significant contributions to the field of high-temperature chlorination of metal ores. Between 1975 and 1995 Dunn consulted to international corporations
Reynolds Metals,
Kerr-McGee and DuPont, among others and performed R&D which formed the bases for several start-up ventures in South Dakota and beyond. He worked with the
Lien Brothers and others in the
Rapid City area to develop processes for the extraction of ultra-pure
niobium from ore, and tantalum metals for use in electronic applications, and for the efficient separation and recovery of gold from low-grade ore and scrap. From the late-1980s until the late-1990s Dunn joined with European and Asian interests to develop a process for low-cost titanium-based pigments, and worked in India for months at a time. He was an adjunct faculty member in metallurgy at the
South Dakota School of Mines and Technology, and was working on a patent application at the time of his death. Dunn had a whimsical side, and in 1979 penned a political satire,
The Sex Tax. Dunn is interred in
Green Mount Cemetery in Baltimore. He was the nephew of civil engineer
Everett Dunn. ==References==