Copper has been making headlines recently, with its price soaring to record highs last week after President Trump announced a 50% tariff on its imports to the US.
And the world's leading miners are deeply invested in the metal due to copper's mass industrial applications and its key role in electrification.
For instance, ASX 200 heavyweight BHP Group Ltd (ASX: BHP) has been building its portfolio of copper projects over the last couple of years.
So much so that today it claims to hold the world's largest copper resource base.
Rio Tinto Ltd (ASX: RIO) – another ASX 200 mining titan – also boasts significant exposure to the red metal through its operations in the US and Mongolia.
And just this week the company reported a lift in production thanks to a ramp up of its Oyu Tolgoi project in Mongolia.
All up, the group's consolidated copper output during the second quarter of 2025 jumped by 9% from the same time last year.
Although the spotlight is often pointed at BHP and Rio Tinto, another copper opportunity may lie elsewhere.
A quiet contender
Investment bank Macquarie Group Ltd (ASX: MQG) sees major upside in a lesser-known ASX 200 copper miner.
And that company is Capstone Copper Corp (ASX: CSC).
The Canadian-based producer operates two mines in Chile, one in Mexico, and another one in the US state of Arizona.
The company also owns a pipeline of growth projects that could see its total copper output rocket in upcoming years.
To illustrate this point, Capstone produced about 184,000 tonnes of copper in 2024.
However, the group is targeting 400,000 tonnes per year via expansion of its current producing assets, as well as the construction of a new Chilean mine, Santo Domingo.
And this upside potential appears to have peaked Macquarie's interest.
Change of direction?
Capstone's share price performance over the past year has likely left investors feeling underwhelmed.
Twelve months ago, its shares were trading at $10.89 each. And yesterday they were going at $8.70 a pop at the close of business.
This represents a decline of 20% over the last year.
In comparison, the All Ordinaries Index (ASX: XAO) is up by about 6% during this period.
But Macquarie believes a turnaround could now be on the horizon.
What are they saying?
On Monday, Macquarie released its research report titled 'Australian copper miners preview'.
Here, the broker put an 'outperform' rating on Capstone with a target share price of $13.30.
This forecast equates to a potential 52% increase in the company's share price from the most recent closing price.
Macquarie cited the prospect for organic growth, valuation upside, and lower guidance risk as its key determinants.
It also noted that the potential sale of a minority stake in Santo Domingo could be an important catalyst for the coming six months.
As such, this under-the-radar copper miner could be in flavour through to the end of the year should Macquarie's crystal ball prove to be true.
