BHP – Olympic Dam
One of the biggest copper discoveries in recent years comes from mining major BHP, 65km southeast from its Olympic Dam exploration programme in South Australia.
In November 2018, BHP made a rare public disclosure of drilling results in the Olympic Dam, revealing “the thickest high-grade copper intersection seen in years.” Laboratory results from this iron oxide copper gold (IOCG) mineralised system showed mineralisation intercepts from 0.5-6.0% copper.
The exploration project is at an early stage, and the company is planning further drilling programmes throughout 2019.
Ivanhoe Mines – Makoko
In October 2018, Canadian mining company Ivanhoe Mines made a high-grade copper discovery west of its Kamoa-Kakula mine in the Democratic Republic of Congo (DRC).
The Makoko discovery is the third major discovery made by Ivanhoe in the DRC, and is the first of a number of high-potential targets in the area to be tested by further drilling.
Drilling at the Makoko discovery has defined a flat-lying, near-surface copper deposit similar to the tier-one discoveries at the Kamoa-Kakula mine.
A joint venture between Ivanhoe Mines, Zijin Mining Group and the DRC Government, Kamoa-Kakula is the world’s fourth-largest copper project, comprising the highest copper grades in the world’s top ten copper deposits.
PT Indonesia – Grasberg
The Grasberg mine in Indonesia is the second-largest copper mine in the world, producing 2.1 million tonnes of copper concentrate in 2018.
In September 2018, Rio Tinto and Freeport-McMoRan gave Indonesia a majority stake in the Grasberg mine through the state-owned mining company PT Indonesia Asahan Aluminium (Inalum). The transaction, expected to be completed in the first half of 2019, will happen once Inalum makes a payment of $3.9m to both companies.
With this transaction Inalum will have 51.2% operating interest in the mine, with Freeport-McMoRan retaining 48.8% interest.
Nevada Copper – Pumpkin Hollow
Pumpkin Hollow is a high-grade skarn/IOCG deposit located in Nevada, with a number of “large metal endowments.” The Pumpkin Hollow project involves the development and construction of an underground mine, with a production rate of 5,000 tonnes per day.
First production at Pumpkin Hollow is anticipated in the fourth quarter of 2019.
Rio Tinto – Resolution
In April 2019, Anglo-Australian multinational Rio Tinto invested an additional $302m into its Resolution copper project in Arizona. With this latest investment, project partners will have invested over $2bn to develop and permit the project since 2004.
The Resolution project is the largest single investment in Arizona’s history, and is expected to meet 25% of the US’ copper demand each year.
It is currently in its seventh year of a comprehensive approval and environmental review process, which is expected to be completed in 2020.
Rio Tinto – Winu
In February 2019, Rio Tinto made a copper-gold mineralisation discovery at its Winu project in Western Australia (WA).
The Winu project is located approximately 130km north of the Telfer mine and 350km southeast of WA’s Port Headland.
Exploration drilling at the project, including eight reverse circulation holes and 20 diamond holes totalling 13,286m, revealed “relatively wide intersections of copper mineralisation.”
The exploration project is still at an early stage, with additional drilling as well as interpretation and assessment of existing data currently planned over 2019.