South Dakota Mines said its century-old Brinell hardness tester has been returned from Rapid City to Tinius Olsen’s headquarters in Horsham, Pennsylvania, where the company will preserve it as part of its history. The university announced the return on Oct. 14, 2026.
The manually operated hydraulic machine arrived at Mines in 1924, when it was acquired for the university’s metallurgical and civil engineering programs, according to the announcement.
Mines said faculty and a graduate student began working nearly a decade ago to restore the tester, which used a hand pump to generate hydraulic pressure and calibrated weights to conduct tests. The restoration could not be completed because worn hydraulic seals could not be replaced, the university said.
The tester was packed as faculty prepared to move equipment into the new Nucor Mineral Industries Building, according to Mines.
Mines said the machine’s serial number indicated it was among the oldest known surviving examples in good condition.
The university said Brinell hardness testing remains an industry-standard method for evaluating metals. Students at Mines continue to study hardness testing in laboratory courses, according to the announcement.
