Cadia Holdings Pty Ltd v New South Wales

The High Court of Australia heard an appeal from the Court of Appeal of New South Wales concerning the ownership of minerals, specifically intermingled gold and copper, extracted from the appellants' lands. The dispute arose from the interpretation of the Crown prerogative regarding "royal mines" and its interaction with the *Mining Act 1992* (NSW) and historical English legislation, namely the *Royal Mines Act 1688* (1 Wm & Mar c 30). The core of the disagreement centred on whether the Crown retained ownership of copper found in conjunction with gold, where the ore body was incapable of being separately mined.

The legal issues before the High Court included whether the *Royal Mines Act 1688* excluded "mines of copper" from the scope of the Crown prerogative recognised in the *Case of Mines* (1568), and whether the mines in question, containing intermingled gold and copper, could be characterised as "mines of copper" for the purposes of that Act. Further, the Court considered whether the common law prerogative, as received in New South Wales, encompassed Crown ownership of intermingled copper, and how the *Mining Act 1992* preserved or modified these prerogative rights.

The High Court allowed the appeal, overturning the majority decision of the Court of Appeal. The Court reasoned that the *Royal Mines Act 1688* did not operate to exclude mines of copper from the Crown prerogative where those mines also contained gold. It applied the principle that prerogative rights are not displaced by statute without clear words or necessary implication. The Court found that the *Case of Mines* established a rule of construction requiring clear words or necessary implication before legislation or a grant could be taken to convey rights to mines of gold and silver. The Court of Appeal's majority had held that the 1688 Act withdrew mines fairly describable as copper mines from the prerogative, even if they contained gold, and that the Cadia mines were not fairly describable as copper mines, thus remaining gold mines within the reduced prerogative, entitling the Crown to their copper. However, the High Court's reasoning, as indicated by the allowance of the appeal, suggests a different interpretation of the interplay between the statutes and the prerogative, likely affirming the Crown's continued entitlement to the copper in such circumstances.

The High Court allowed the appeal with costs and set aside the orders of the Court of Appeal, dismissing the appeal to that Court with costs.