The mine is located two kilometres east of Wilberforce on lot four, concession 21 of Cardiff Township.

[3] His find was first called "the Richardson deposit" and later "the Fission property"[4]: 175 In 1929, the mine was owned by Toronto company The Ontario Radium Corporation.

[2] The same year, Ontario Mine's Branch geologists Hugh S. Spence and R. K. Carnochan reported the several hundred pounds of radioactive materials found exceeded all known quantities of uranium in Canada and all ore bodies that they were aware of anywhere in the world.

[2] Combined with being close to the surface, and easier to mine due to being held in softer ore, the mine was assessed as being commercially viable and able to produce 1 gram of radium, worth $70,000 at the time.

[2] Between 1929 and 1931,[4]: 175  unsuccessful[5] attempts were made to extract radon from the uranium ore[6] via a tunnel driven into a hill.