ASX mining share Locksley Resources Ltd (ASX: LKY) has exploded in 2025, ripping 2,840% higher to close at 50 cents on Friday.
The critical minerals explorer hit a record 69 cents per share on 22 September, which represented a 3,959% climb in the year to date.
So, what's putting a rocket under this ASX stock?
Everything you need to know about this ASX mining share
Locksley Resources is a critical minerals explorer targeting rare earths and antimony in the United States.
It also has a copper and gold mine in NSW, but the US is its key focus right now.
Locksley Resources is seeking to leverage the US Government's strong desire for a domestic supply of critical minerals to support its defence, technology, and clean energy sectors and reduce its reliance on Chinese suppliers.
Locksley's flagship Mojave Project in California's Mojave Desert has rare earths, antimony, and potentially other metals, including high-grade silver. China is currently the world's biggest supplier of these critical minerals.
The Project is in a Tier One location adjoining the Mountain Pass Project.
Mountain Pass is one of the world's highest grade rare earths mines and the only producer in the US. It's owned by MP Materials Corp and backed by the US Department of Defense and Apple Inc.
Locksley has permits for drilling and full funding in place for two of its explored sites, El Campo and Desert Antimony.
El Campo has rare earths, with rock chip grades up to 12.1% total rare earth oxides (TREO).
Those oxides include Neodymium-Praseodymium (NdPr) of up to 3.19%. NdPr are two rare earth elements used in an alloy to produce high-performance magnets. These magnets are essential for wind turbines, electric cars, robotics, and defence systems.
The historical Desert Antimony Mine (DAM), which includes an on-site processing smelter, last operated in 1937. DAM has returned surface assays as high as 46% Sb (antimony) and outcropping quartz-calcite-stibnite veins.
Antimony is a metalloid, which means it has both metal and non-metal properties. It is used in an alloy to make lead-acid batteries and bullets. It makes low-friction metals stronger and harder. It's also used as a flame retardant in plastics, textiles, and electronics.
Antimony is not currently produced in the US, but is an essential ingredient for defence, industrial, and semiconductor applications.
Also, Locksley has partnered with Rice University in Texas to explore antimony's potential use in advanced energy storage systems.
What's been driving Locksley Resources shares higher in 2025?
Investors have been excited by a slew of excellent assay results, as well as drilling approvals for El Campo and Desert Antimony.
Locksley says its Mojave Project is "emerging as a district-scale critical minerals hub".
Assays indicate a broader polymetallic system beyond rare earths and antimony, including silver, zinc, lead, and copper.
Last month, Locksley Resources announced it had doubled its landholding at Mojave and increased its claims from 242 to 491.
Two capital raises in 2025 have given the company enough funding to commence drilling at El Campo and Desert Antimony.
On Friday, Locksley announced a 400% increase to the target mineralised corridor at Desert Antimony Mine (DAM) to 1.2 km.
The explorer said a metallurgical test work program on surface samples produced high-grade concentrate of up to 68.1% antimony.
This significantly exceeds the minimum marketable sales requirement of 55%.
Last month, Locksley received a NATO Commercial and Government Entity (NCAGE) Code.
This is required for participating in US and allied government contracting and funding programs. It means the explorer can now engage directly with the US departments of defence and energy for critical minerals funding.
In June, Locksley Resources completed an OTCQB listing in the US to improve local investor access and visibility. It also listed on the Frankfurt Stock Exchange to elevate visibility in Europe.
Last month, the company appointed a new CEO, Kerrie Matthews, and COO, Danny George.
Their first priority is fast-tracking a mine-to-market strategy for antimony in the US.
Matthews has more than 20 years of experience delivering complex projects. She was involved in South Flank for BHP Group Ltd (ASX: BHP) and Australia's first fully integrated rare earths refinery, Eneabba, for Iluka Resources Ltd (ASX: ILU).
Should you buy this ASX mining share?
Niv Dagan from Peak Asset Management has a hold rating on Locksley Resources shares.
Dagan noted the ASX mining share's skyward rise from 22 cents on 9 September to 50 cents on Friday after a bunch of positive announcements last month.
He explained his rating on The Bull late last month:
We retain a hold recommendation as some profit taking could occur in response to the rapid share price rise.
He may have been right, given Locksley Resources shares have fallen from a record 69 cents on 22 September to 50 cents on Friday.
