Grundt v Great Boulder Pty Gold Mines Ltd

Grundt v Great Boulder Pty Gold Mines Ltd [1937] HCA 58

When an estoppel arises.

Facts

The appellants entered into an agreement in June 1934 with the respondent mining company to mine gold ore in a certain area. The mining company provided facilities, processed and sold the ore, giving the miners one half share in the gross profits of sale. The appellants exceeded the agreed area that was to be mined. When the company found out in May 1935 it complained but continued to receive the ore and pay the appellants. This continued until August 1936, when the mining company cancelled the agreement.

Issues

The appellants argued that the mining company were estopped from cancelling the agreement or had waived their rights because they had already received and processed the ore and provided essential mining equipment. The respondents claimed the appellants were entitled to nothing because they had exceeded the agreed mining area under the agreement.

Decision/Outcome

The High Court of Australia held that the company was estopped from claiming back a share of profits after they had complained about the appellants mining outside the agreed territory, but could claim back the share of profits they had parted with before they had complained. Latham CJ held that the appellants were induced to act to their detriment by working due to the company’s conduct which gave their apparent consent. He said there was some overlap between estoppel and waiver, by which a person abandoned their rights. Dixon J said that the claimant’s original position only operates as a detriment at the moment the person gives an assurance. By consenting to further mining operations, the company had given such an assurance.