Characterisation of gravity amenable gold ores - Sample representivity and determination methods

S. C. Dominy, B. Murphy, A. H. Gray

Research output: Chapter in Book/Report/Conference proceedingConference PaperResearchpeer-review

15 Citations (Scopus)


Gravity amenable gold ores are those that after comminution produce liberated particles, composites and/or carriers that can be recovered by gravity separation means. Recovery depends upon mineralisation type and the comminution and concentration method used. Any in situ ore with more than 20 per cent of gold greater than 100 μm in size is likely to have a strong gravity recoverable component. A less traditional approach is where the gold is sulfide-locked and the gold carrier plus any liberated gold is recovered via continuous gravity recovery following fine crushing. Specific tests are undertaken to determine the level of gravity amenable gold within a deposit. The principal methodology is the gravity recoverable gold (GRG) test, which consists of three sequential liberation and recovery stages. For continuous gravity recovery (CGR), the sample is fed over a laboratory Wilfley table to simulate continuous recovery of the gold. Tails from the feed can be progressively re-ground and re-tabled to develop a grade-recovery curve. Primary geology and gold particle size-distribution have a strong effect on the mass of sample required to provide representative results for both tests. Where low-grade ore contains very coarse gold, substantially larger sample masses are required. Experience has shown that GRG and CGR values can vary throughout an orebody, particularly within different geological-grade domains. A testing regime must consider sample frequency and support.

Original languageEnglish
Title of host publicationGeoMet 2011 - 1st AusIMM International Geometallurgy Conference 2011
Number of pages12
Publication statusPublished - 2011
Externally publishedYes
EventInternational Geometallurgy Conference 2011 - Brisbane, Australia
Duration: 5 Sept 20117 Sept 2011


ConferenceInternational Geometallurgy Conference 2011
Abbreviated titleGeoMet 2011
Internet address

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