THE KAPUNDA MINE
KAPUNDA - SOUTH AUSTRALIA
The Kapunda mine is located in the core of a northwest-trending anticline comprised of metasediment.
Three vertical zones were identified: The upper impoverished zone extending to a depth exceeding 50 meters, comprised of leached ore minerals; The lower secondary enrichment zone is around 40 meters thick, reaching around 90 meters; The third and final zone reaching around 30 meters of primary sulphides, the zones shallow to the north.
TAPLEY HILL FORMATION
Siltstone, grey to black, dolomitic and pyritic grading upwards to calcareous, thinly laminated, locally cross-bedded; dolomite, grey, flaggy to massive; limestone conglomerate, intraformational; greywacke.
The Tapley Hill Formation is heavily kaolinised, fine-grained and is metasedimentary,
dolomitic siltstone, minor arkose and shale.
Min & Max: Sturtian
The vein systems extended for 730 meters, and to a width of 150 meters, these veins were worked to around a depth of 146 meters.
The most high-grade ore occurred in quartz veins in kaolinised “shoots.” The lodes occurred in a system of three main collections of veins, the most productive was trending in an NNE direction. The Tapley Hill Formation which hosts the veins is also mineralised but to a much lower degree. The individual ore shoots were around 0.45-1.20 meters wide, and from 45 to 60 meters long.
The Arches are visible behind the gates leading into the Stockyard Open Cut, they were most likely cut out during mining efforts and not as a natural erosional feature formed after the closure of the mine.
This is because a tunnel leads into the Tapley Hill Formation behind both arches and not enough time has elapsed for that type of erosion and collapse to have occured.
Discovered in 1842, and now a very significant mine to the state of South Australia, The deposits were related to regionally metamorphosed rocks in a structural-fault, shear, and fracture zone. Early miners recognised an observational relationship between the more highly mineralized areas and the amount of kaolinisation.
The first ore was raised to the surface in 1844 by shovelling the blue/green outcrop into carts, a few months after that underground mines had also begun expanding, by December of that year. During its first 5 years of operation, ore was carted to Port Adelaide and shipped to and smelted at Swansea in Wales. The Kapunda Mine was forced to close in 1851 and re-open in 1855 as the mining towns population dwindled as the Victorian Gold Rush began.
From the beginning and to the end of operations 69,000 tonnes of ore was yielded, 13,700 tonnes of that ore was copper. Copper production peaked in 1857 with ore being transported overseas, smelting works were commissioned around 1852 when an impure metallic form of substance was produced through (reduction) for shipment, later a refining unit was added for the production of high-grade copper products.
During the final stages of operation from 1869 to 1878, a leaching process was added to treat the much lower grade 2.5% copper ore, this produced copper cement until its final days of operation. Mining ceased in 1878 when an eastern drive from the Harris shaft hit the water table at 146 meters, the water flow exceeded 1.3 million litres per day. The ore deposit was worked on occasion until 1912 by miners that worked on small amounts of ore above the water table.
From Newspaper Articles:
"Francis Dutton, separately discovered copper ore on the surface of the ground, in the county of Light, about 45 miles north from Adelaide. Mr Dutton and Captain Bagot afterwards agreed to purchase the section of 80 acres, keeping of course the secret, and they have thus become, for the sum of £80, the fortunate proprietors of, apparently, one of the most valuable copper mines which has been discovered in any part of the world. Captain Bagot transmitted specimens of the ore to London, for the purpose of being assayed, and received in reply the following highly favourable report of an assay by Mr Percival Johnson:
Carb. Acid ...........................................18¾
Oxide of Iron ...........................................21
Earthy matter, chiefly Silex ..................19/100
At which percentage of copper the ore was worth £27 per ton. This mine has been called the Kapunda Copper Mine. Even after the above report, people paid very little attention to the discovery." - The Southern Australian, 22nd of March 1844."
The Kapunda Copper & Gold ISR Project
The latest project to work on the Kapunda Copper Mine started up in 2016 after the permits were agreed through Terramin Ltd. Funding was negotiated with Thor Mining in several stages which incorporated EnviroCopper Pty Ltd during August in 2017. The Light Regional Council approved EnviroCopper to start early-stage investigations in February of that year. In February of 2019, a Joint Venture Agreement was signed and lodged with Terramin Ltd. and with the Department for Energy & Mining (DEM).
With enough historical drilling data from 1965 to 2008, a calculation of the inferred copper could be estimated which came around to 119,000 tonnes. Historical water sampling data indicated that significant amounts of copper are located within the mine's groundwater.
The project is expected to take place in stages and to be in accordance with the South Australian Mining Act of 1971. EnviroCopper was awarded a Commonwealth Government Co-operative Research Centre Grant (CRC-P) in Copper & Gold In-Situ Recovery Mining that was worth $2.8 Million which will fund more research for better environmental outcomes. By 2021 improved economic results and community engagement is expected.
The underground workings cover an area of one kilometre in length in an NNW-trending zone.
A number exceeding more than 29 separate productive ore veins were recorded, various productive branch veins were mined from at least 15 separate vertical shafts. The main lode they were chasing dipps to 30-45° and towards 250° degrees.
In 1845 the underground workings hit the water table, a horse and whim was installed for bailing the water out. By 1847 the horse-drawn whim was incapable of drawing the water out as the shafts got too deep and the water volume was increased, because of this a steam engine was bought and transported from England. A second engine only used for pumping was also installed in 1850.
STOCKYARD OPEN CUT
Operations began in 1866
South Australian Government. (n.d.). SARIG geological map. SARIG.
The South Australian, Adelaide, SA: 1838 - 1844. (1844, March 22). The Mining Interest. Trove.
EnviroCopper. (n.d.). The Kapunda Copper & Gold ISR project | EnviroCopper. Environmental Copper Recovery SA Pty Ltd.
Cowley W.M. and Preiss, W.V. (2016). Mineralisation in the Mid-North. Geological field excursion guide — Rifts, reverse faults and regolith: Neoproterozoic to Cenozoic geology in the Mid-North of South Australia. (pp. 22–26). Report Book 2016/00013. State Development, South Australia; and Geological Society of Australia, South Australia. SARIG.
South Australia Department of mines and Energy and Natural Resources. (1990, January). Kapunda Mine, 1–4.