Fox, N and Parbhakar-Fox, A and Lottermoser, BG, Critical and deleterious metal deportment in sulfidic waste rocks, Baal Gammon, north Queensland, Proceedings of the 3rd AusIMM International Geometallurgy Conference 2016, 15-16 June 2016, Perth, Australia, pp. 173-182. ISBN 9781925100457 (2016) [Refereed Conference Paper]
Official URL: http://www.geomet.ausimm.com.au/
Determining the deportment of economic and environmentally significant elements in sulfidic mine materials (eg ore, gangue and waste) requires the use of advanced microanalytical techniques, including electron microprobe analysis (EMPA) and laser ablation inductively coupled plasma mass spectrometry (LA-ICPMS). Sulfidic boulders were sampled from an acid rock drainage impacted ephemeral stream adjacent to historical copper-silver workings at Baal Gammon, northern Queensland. The abundance and deportment of a range of trace elements and precious metals were analysed in these samples. Whilst many of these elements represent a potential environmental risk if leached from sulfidic rocks into streams in the surficial environment, significantly some of these elements (eg In, Sb and Co) represent specialised metals that are currently considered to be in critical supply.
Sulfidic waste rock material at Baal Gammon is dominated by chalcopyrite, arsenopyrite, pyrrhotite and pyrite. Microanalytical investigations revealed that chalcopyrite contains significant quantities of In, Sn, Ag and Zn either substituted directly into the crystal lattice or occurring as discrete sphalerite and stannite inclusions. Arsenopyrite, which may comprise more than 50 per cent of some boulders, is notably enriched in Sb, Co and Ni but also contains inclusions of sphalerite, chalcopyrite and stannite. In contrast, pyrrhotite contains no trace elements of economic significance, but instead represents a likely contributor to acid generation during oxidation in the surficial environment. Trace metals (eg In, Sb, Co, Ni, Zn) are liberated during sulfide oxidation of these boulders in the surficial environment, generating a metal-rich, low-pH leachate. Fe-oxides precipitated as rinds on the surface of these boulders under low pH conditions also contain abundant As, Bi, Sn, Cu and Zn. Abandoned or historical mines represent potential sources of metalliferous drainage that poses potential environmental risks to water and habitats. However, sulfide-rich historical waste rock, stockpiles and processed waste (eg tailings) at abandoned mines may also represent significant sources of critical (eg indium) or other significant metals (eg Sn) that if liberated economically could improve environmental conditions in and around abandoned and historical mines.
|Item Type:||Refereed Conference Paper|
|Keywords:||waste rock, indium, sulphide, microanalysis, Queensland|
|Research Division:||Earth Sciences|
|Research Field:||Exploration Geochemistry|
|Objective Group:||Land and Water Management|
|Objective Field:||Mining Land and Water Management|
|Author:||Fox, N (Dr Nathan Fox)|
|Author:||Parbhakar-Fox, A (Dr Anita Parbhakar-Fox)|
|Deposited By:||CODES ARC|
Repository Staff Only: item control page