Ore genesis and loses its metal carrying capacity. Ore deposits rarely fit neatly into the categories in which geologists wish to place them. Many may be formed by one or more of the basic genesis processes above, creating ambiguous classifications and much argument and conjecture. Often ore deposits are classified after examples of their type, for instance Broken Hill type lead-zinc-silver deposits or Carlin–type gold deposits. Classification of hydrothermal ore deposits is also achieved by classifying according to the temperature of formation, which roughly also correlates with particular mineralising fluids, mineral associations and structural styles. This scheme, proposed by Waldemar Lindgren (1933)
Heavy mineral sands ore deposits Chile and Ecuador, is carried out in an environmentally responsible manner. Examples of environmentally sensitive and politically sensitive mineral sand mining operations which have gained public attention and galvanised environmental activism responses to mining proposals include the Tuart-Ludlow mineral sands mine, Western Australia, and the culmination of conservationist efforts to preserve Rainbow Beach and Fraser Island, Queensland, Australia. These latter campaigns successfully lobbied government and saw Fraser Island and Rainbow Beach protected by the High Court of Australia; however, the Tuart-Ludlow campaign failed to prevent mining works in the Tuart forests in coastal Western Australia. Similar mineral sand mining operations