Mt Freda Gold Mine, Australia
Mt Freda is a gold mine located 39km south-east of Cloncurry in Queensland, Australia. Production at the mine was halted when gold prices fell below $240oz in 1991.
Queensland Mining (QMC), the owner and operator of Mt Freda, undertook drilling at the mine in November 2009 in order to recommence production. Results revealed substantial commercial potential. QMC will begin production upon completion of the metallurgical recovery test and economic scoping study.
The project consists of two granted mining leases over an area of 120ha.
Geology and reserves
The mine hosts over 100,000oz of gold. It lies in the Cloncurry district, which is characterised by Paleoproterozoic cover sequence rocks. Rock sequences in this zone are intruded by a number of metamorphic intrusions that are predominantly potassic in nature.
The mine contains a high-grade zone of mineralisation along a 350m-long strike length. Located at a depth of 150m, the zone remains open to the east and west along strike and at depth. It hosts ore bodies that contain copper and cobalt.
By 1991, the mine had been drilled to a depth of 60m with 46 holes. The strike length of the mine was, however, not fully explored during that time. At Mt Freda, gold mineralisation extends with the depth.
To extend the known mineralisation, QMC commenced further drilling in November 2009. The first phase included a 50-hole drill programme that was carried out with over 10,000m of reverse circulation and diamond core drilling. The maximum width of the downholes was 40m at a depth of 133m.
Core samples obtained from the drilling were assayed at a laboratory in Townsville. Results from the assay revealed the presence of significant gold and cobalt resources.
A drilling programme was undertaken on 4-16 June 2010. Around 16 reverse circulation holes were designed to upgrade the existing resources to measured or indicated category for future mining. Most of the holes were drilled perpendicular to the intercepted NWW-SEE trending structure at an angle of -55 degrees. The depth of the holes varies from 84-192m.
Ore is processed in a carbon-in-pulp treatment plant available on site. A large amount of infrastructure, including a headframe, winding circuit and mines-compliant shaft, installed during earlier mining operations, is available on site. A carbon stripping and electro winning plant is installed at the Gilded Rose prospect located 20km north of Mt Freda. The Gilded Rose prospect is also equipped with a CIP batch plant. The plant comprises a two-stage crushing circuit, grinding mill, circuit and a 200t leach tank that contains mixing as well as a pumping circuit.
Additional construction at the site will include a heap leach treatment circuit. Given the high price of gold, the heap leach treatment circuit will process low grade +2g/t Au oxide ore stockpiled at the mine. The mine hosts 150,000t of low grade and previously mined ores at its surface. A recently purchased crushing plant will be erected on site to treat the stockpiled ore.
Mt Freda Group
The Mt Freda Group includes five connected mining leases including the Mt Freda and Evening Star mining lease. The total area covered by these leases is more than 142ha.
QMC owns a portfolio of over 50 granted mining leases in the Cloncurry mineral region. This includes granted mining leases in the mineral fields towards the south of the Cloncurry zone, within Ivanhoe Selwyn EPM and Mt Isa Mines Young Australian copper mine. It also owns a number of mining leases around the massive Mary Kathleen Uranium mine and previously drilled Flamingo Mining leases situated towards the north of Cloncurry mineral zone.