Skip to main content
Conference Proceedings

Tenth International Mining Geology Conference 2017

Conference Proceedings

Tenth International Mining Geology Conference 2017

PDF Add to cart

Challenges of bi-modal gangue mineralogy in mining geology

The Avebury nickel mine in Western Tasmania is a disseminated nickel sulfide deposit hosted in intensely metasomatised Cambrian ultramafic resulting from later Devonian granite related hydrothermal activity.Variable metasomatism of the ultramafic has formed two distinct gangue mineral assemblages. Less metasomatised ultramafic is comprised of fine grained black antigorite with minor disseminated chromite, magnetite and pentlandite. Intensely metasomatised ultramafic is altered to a pale grey or green, coarsely crystalline tremolite/actinolite and diopside assemblage with minor magnetite, chromite and sulfides. Both gangue mineral assemblages are frequently intermixed in ore grade mineralisation.The bimodal gangue of either serpentinite or metasomatised ultramafic presents challenges to drilling, mining, resource estimation and mineral processing as they possess very different physical properties. Mineralised serpentinite has a mean bulk density of 2.8 g/cc and the ultramafic skarn a mean bulk density of 3.2 g/cc. Physically, the ultramafic skarn is hard to break percussively creating difficulties in the crushing circuit and reducing mine development rates. However, it is non-abrasive and grinds readily, resulting in increased diamond drilling rates and increased mill throughput. Conversely the serpentinite gangue is softer and breaks easily resulting in accelerated development rates and crushing circuit throughput. However, its fibrous nature reduces grinding efficiency, increasing bond work indices and reducing diamond drilling rates.Predicting the ratio of serpentinised to metasomatised ultramafic is possible through use of the resource blockmodel, assisting mine scheduling, predicting mill throughput rates, energy consumption and grade control drilling rates.CITATION:Callaghan, T J, 2017. Challenges of bi-modal gangue mineralogy in mining geology, in Proceedings Tenth International Mining Geology Conference 2017, pp 23-26 (The Australasian Institute of Mining and Metallurgy: Melbourne).
Return to parent product
  • Challenges of bi-modal gangue mineralogy in mining geology
    PDF
    This product is exclusive to Digital library subscription
  • Challenges of bi-modal gangue mineralogy in mining geology
    PDF
    Normal price $22.00
    Member price from $0.00
    Add to cart

    Fees above are GST inclusive

PD Hours
Approved activity
  • Published: 2017
  • PDF Size: 1.83 Mb.
  • Unique ID: P201707004

Our site uses cookies

We use these to improve your browser experience. By continuing to use the website you agree to the use of cookies.