Deposits with economic tin (Sn) or tungsten (W) – molybdenum (Mo) are widespread in north-east Queensland, ranging between -14.40 and -19.50°and 143.50-146.20°. This area used to be one of the major sources on Sn and W in Australia, with mineralisation discovered and exploited from the 1880s. According to the Geological Survey of Queensland (GSQ) database (von Gnielinski, 2015) this region has 792 Sn deposits and 132 W deposits. The large number indicates that geological conditions are generally favourable for Sn-W-Mo mineralisation; however, this area contains less than 10% of Australia's Economic Demonstrated Resources (EDR) of Sn and <13% of the country's EDR of tungsten (Britt et al, 2015). The deposits are generally small compared to the giant deposits of other parts of the world. For example, the Dahutang tungstenand the Gejiu tin deposits in China contain ~1 Mt W and ~3 Mt Sn (non-JORC compliant), respectively (Cheng et al, 2013; Mao et al, 2013).
The deposits have different metal associations and can be classified into W-dominant, W-Mo-Bi, and Sn-dominant deposits. These subtypes also have distinctive features and time–space distributions. The deposits are summarised below using this scheme for first-order classification.