Primary and secondary high-grade gold mineralisation processes in orogenic systems: key to a sustainable mining?

The Challenge

Zones of gold mineralisation can sometimes contain tiny and/or irregularly distributed veins of ultra-high-grade gold. Where present, these high-grade intervals can significantly improve mine profitability, but current models of gold transport and deposition do not account for their formation. This leaves the presence and distribution of these zones unpredictable, posing a challenge for industry exploration and resource estimation. 

Key Findings 

A new model for the development of ultra-high-grade gold mineralisation as a consequence of multiple interacting chemical and physical processes has been defined.  

Discrete high-grade concentrations of gold accumulate where sustained fluid flow, rock deformation, and repeated remobilisation of gold coincide. 

Additional significance comes from previously unappreciated phenomena including the development and mechanical behaviour of gold nanoparticles, and the influence of deformation-induced electricity, crystal defects, and silica chemistry in the precipitation and remobilisation of gold within mineralised zones. 

Benefits to WA 

Improved understanding of the formation and distribution of high-grade gold mineralisation will help the WA gold industry improve the quality and accuracy of resource estimation, reducing the footprint and improving the profitability of future mines. 

DOI

10.71342/232918258291