Very few investors had heard of Dateline Resources Ltd (ASX: DTR) at the start of the year.
In early January, shares in this ASX mining stock were changing hands at $0.003 per share, with its market capitalisation clocking in at less than $10 million.
At the time, Dateline was one of hundreds of tiny mineral explorers hoping to make its mark.
But make its mark it did.
Fast forward to today, and shares in this ASX mining stock closed out Thursday's session at $0.495 apiece – up by a stunning 16,400% since the start of the year.
To put that in perspective, the broader All Ordinaries Index (ASX: XAO) has risen by 9.6% over the same period.
And Dateline's market capitalisation has now soared to more than $1.6 billion.
Let's take a closer look at the driving forces behind this spectacular transformation.
California dreaming
Dateline owns the Colosseum gold and rare earths project in the US state of California.
Firstly, let's start with the gold.
The price of the metal has been soaring to new heights in 2025, recently breaking the US$4,000 per ounce barrier for the very first time.
And historically, Colosseum was a producing gold mine.
It churned out more than 340,000 ounces of the metal until its closure in 1993, when the price of gold was just US$340 per ounce.
So, today's strong pricing environment presents an opportunity for Dateline as it seeks to revive the mine.
Colosseum still holds a resource containing 1.1 million ounces of gold, and an early-stage economic assessment suggests that mining could be warranted at contemporary gold prices.
Dateline's recent scoping – using a gold price of US$2,900 per ounce – pointed to a nine-year mining operation producing about 71,000 ounces annually.
It forecast total sales revenue of more than US$1.7 billion, with an all-in sustaining cost (AISC) of US$1,490 per ounce.
The net present value (NPV) came in at US$550 million, with an internal rate of return (IRR) of 61%.
In addition, management sees significant potential for additional gold discoveries at the project.
But gold is only half of the story for Dateline.
The other half is the rare earths potential at Colosseum.
Critical minerals
Rare earths are a group of 17 elements used in a wide range of industries, including clean energy, automotive, electronics, and robotics.
In particular, neodymium and praseodymium are critical components in permanent magnets used to power electric vehicles (EVs), wind turbines, and consumer electronics.
China produces about 95% of all the world's rare earth magnets and processes some 90% of all rare earth metals.
And this concentrated supply is pushing some Western nations to find new sources of rare earths for their own economies.
For example, the US has designated several rare earths as critical minerals, including neodymium and praseodymium.
And here's the interesting thing.
Colosseum lies only 10 kilometres from Mountain Pass – the only operating rare earths mine in the US.
So what?
Recent studies by the US Geological Survey concluded that Colosseum shares a geological connection with Mountain Pass.
In other words, the same rock formations that host rare earth mineralisation at Mountain Pass could also exist at Colosseum.
Furthermore, results from Dateline's early-stage exploration supports the potential for rare earths mineralisation at the project.
Curiously, these findings have not gone unnoticed at the highest levels of US government.
In fact, President Trump publicly endorsed the project, hailing Colosseum as "America's second rare earths mine".
Such government backing has helped Dateline secure federal approvals to recommence mining at Colosseum.
What's the catch?
It warrants mentioning that the company has not yet defined a rare earths resource at Colosseum that is economically viable to mine.
And there are no guarantees that it ever will.
Separately, Dateline is currently conducting a more detailed economic evaluation of Colosseum's gold system.
The results of this analysis will determine whether developing a gold mine is a worthwhile endeavour.
This study will also provide insight into the potential construction costs, which could run into several hundred million dollars.
So, the journey to producing gold and rare earths at Colosseum is filled with risks and uncertainty.
As present, mining remains a distant proposition and not an immediate reality.
