Howard Tracy Hall (October 20, 1919 – July 25, 2008) was an American physical chemist and one of the early pioneers in the research of synthetic diamonds, using a press of his own design.

Hall returned to the University of Utah in 1946, where he was Henry Eyring's first graduate student, and was awarded his PhD in physical chemistry in 1948.

He joined a team focused on synthetic diamond making, codenamed "Project Superpressure" headed by engineer Anthony Nerad.

These years had seen a succession of failed experiments, an increasingly impatient management, and a complex blend of sharing and rivalries among the researchers.

He "bootlegged" the machining of the first hardened steel version of this press, which showed some promise, and eventually got management to approve the construction of it in the tougher, much more expensive Carboloy (tungsten carbide dispersed in cobalt, also known as Widia).

Hall used iron sulfide and a form of powdered carbon as the starting material, with tantalum disks to conduct the electricity into the cell for heating it.

[4] Upon breaking open the sample, clusters of diamond octahedral crystals were found on the tantalum metal disks, which apparently acted as a catalyst.