He graduated in mining from the Royal College of Science in Dublin, and in 1870 was appointed as a geologist in the Geological Survey of Ireland.
The British Colonial Office chose Hardman for the position, and he arrived in Perth, Western Australia in March 1883.
Hardman found traces of gold throughout the east Kimberley, especially in the area around the present-day town of Halls Creek.
Hardman's map and report were heavily relied upon by prospectors, and held in high regard.
The field's Warden, Charles Price stated Back in 1872, the Government of Western Australia had offered a reward of £5000 for the discovery of the colony's first payable goldfield, with a number of conditions attached.