Up to 1,200 samples from 27 drill holes from drilling progammes between 2012 and 2017 are to be re-assayed, Thor announced.
The tests will be run on drill samples from each of the Desert Scheelite, Garnet and Good Hope deposits.
The decision was taken after test work conducted on 600 kilograms of drill core from the Desert Scheelite deposit revealed for the first time, as announced in mid-June, the presence of potentially economic levels of gold in the sample.
Testing for the presence of gold has not been routinely performed on samples from Pilot Mountain, either by Thor or previous permit holders; until these follow-up assays on the historical drilling are available, it is uncertain if gold will have a material economic impact on the project.
"This is potentially a very exciting phase for our 100% owned Pilot Mountain project," said Mick Billing, the executive chairman of Thor.
"In the event that gold appears with any consistency in the Pilot Mountain deposits, we may have a step change of substance for this project," he added.