The Iron Knob mining area (IKMA) lies at the northern end of the Middleback Ranges (MBR).

• Hosted within the Palaeoproterozoic Hutchison Group metasediments.
• Mineralization is within the Lower Middleback Iron Formation grades upwards from Carbonate Haematite to Jaspilite Haematite facies.
• Ore Formation is considered through passive supergene enrichment of Magnetite Banded Iron Formations.
• Strongest Enrichment within the LMIF Carbonate Facies – leading to complete replacement of carbonates in highest grade zones.
• The Metasediments have a history of complex deformation dominated by East – West compression.
• Mineralised zones are bounded to the East and West regional scale North – South Shear Zones.
• Multiple Stages of Archean amphibolite dykes cross cut both deposits and are influence on mineralisation and Geotechnical Parameters.

Middleback Ranges Hematite
Hematite in the MBR occurs as stratabound Palaeoproterozoic deposits of the Lower Middleback Iron Formation (LMIF), part of the Hutchison Group. The Hutchison Group forms part of the Cleve Subdomain of the Gawler Craton, and lies on its western edge. The Cleve Subdomain comprises tightly folded high-grade metamorphic rocks that are mainly derived from marine shelf sediments and mafic and acidic volcanics (Parker, 2012b).

Middleback Ranges Framework In the MBR, the Hutchison Group is composed of the Warrow Quartzite and the Middleback Subgroup. ........

Operations throughout the reporting period (FY 2020) continued the recovery and processing of low-grade stockpiles through the Integrated Processing Facility (IPF) and deposition of tailings into the Monarch void as approved under PEPR 2017/004.

SIMEC Mining placed the IKMA operations into care and maintenance on 1 July 2018. The decision to suspend operations at IKMA was a result of high production costs and ongoing low iron ore prices and part of SIMEC’s overall business response to this business environment. It was envisaged that mining operations would re-commence at some point following a sustained increase in the price of iron ore to a point at which the mine again becomes economically advantageous to operate.

While other areas of the IKMA are in a care and maintenance phase, SIMEC Mining are proposing to undertake scree mining operations.

Mining of scree ore will supply feed to SIMEC’s Integrated Processing Facility (IPF). Current (2020) IPF feed is from reclamation of historic low-grade dumps. The scree ore will supplement the low-grade feed and on depletion of stocks, will replace the low-grade feed altogether. During Monarch Scree mining operations, feed to the IPF is expected to be approximately 135 wet mass kilotonnes per month. A significant stockpile of IPF feed (approximately 100 kilotonnes) will be maintained, in order to feed the processing facility during times of mining cessation, due to detrimental weather conditions or ot ........

- subscription is required.

- subscription is required.