The Thames School of Mines was established in 1886 to train engineers and managers for the hard-rock goldfields of the Coromandel. Its graduates worked mines across New Zealand, Australia, and the Pacific, and the surviving complex is one of the country's best preserved mining-school sites.
The museum is small but excellent: assay equipment, ore samples, survey drawings, furnaces, laboratories, and mineral collections still sit in rooms that feel close to their working state. It gives a clearer sense than almost anywhere else in town of how technical the Thames goldfield became once the easy surface gold was gone.