Geophysics Converge Ahead of Colosseum Deeper Drill Program

Rhea-AI Summary

Dateline Resources (OTCQB:DTREF) completed infill gravity, magnetic and radiometric surveys at its 100%‑owned Colosseum Gold and Rare Earth Project, following an IP survey in Dec 2025. The datasets (543 gravity stations; 8.6 km² magnetic/radiometrics) are being integrated to refine targets before diamond drilling scheduled to start next week.

The integrated interpretation aims to finalise priority targets at depths of approximately 500–1,000 metres, with Mitre Geophysics assisting data integration and drill planning ongoing.

Positive

• Completed high‑resolution surveys: 543 gravity stations on 100m grid
• Magnetic/radiometric coverage of approximately 8.6 km² enhances target resolution
• Integrated datasets aim to convert broad targets into focused drill targets
• Diamond core drilling rigs scheduled to arrive on site next week

Negative

• Priority targets at ~500–1,000 m depth indicate more technically demanding drilling
• Deeper drill testing likely increases capital and operational cost requirements

Infill Geophysics Surveys Completed at Colosseum Project

SAN BERNARDINO, CALIFORNIA / ACCESS Newswire / February 9, 2026 / Dateline Resources Limited (ASX:DTR)(OTCQB:DTREF)(FSE:YE1) is pleased to announce the completion of infill gravity, magnetic and radiometric surveys at its 100%-owned Colosseum Gold and Rare Earth Project in California, USA. This follows the completion of an induced polarisation (IP) survey across the project in December 2025.

All newly acquired geophysical datasets are being integrated to progressively sharpen drill targeting across the key structural corridors identified by earlier programs. This work is expected to transition the Company from broad-based target definition to highly focused drill testing. Diamond core drilling rigs are scheduled to begin arriving on site next week.

Infill Geophysics Program - Scope and Completion

The infill program completed was comprised of:

• A high-resolution ground gravity survey consisting of 543 stations collected on a 100 m × 100 m grid, providing detailed density coverage across the central project area.

• A magnetic and radiometric survey at 50m line spacing covering approximately 8.6 km² delivering high-resolution magnetic and radiometric datasets.

The surveys were designed to improve resolution over areas where earlier IP and MT data identified deep chargeability and conductivity features interpreted to be structurally controlled and potentially associated with gold mineralisation and/or REE-bearing carbonatite intrusions.

Dateline's Managing Director, Stephen Baghdadi, commented:

"The data continues to support the presence of a large mineral system, with deep structural and sulphide-hosted features interpreted as mineralising plumbing extending beyond the known near-surface ore zones. The integration of these high-quality geophysical datasets is a deliberate step to sharpen drill targeting and maximise the effectiveness of the forthcoming drilling campaign. With several targets interpreted at depths of approximately 500-1,000 metres, this approach ensures that drilling is highly focused, technically informed and capital-efficient as the Company advances into deeper, more technically demanding drill testing."

Figure 1: Preliminary TMI Magnetics from the recently completed survey at Colosseum. The colours represent variations in magnetic susceptibility within the shallow subsurface. Red and pink zones indicate magnetic highs reflecting magnetite bearing intrusive rocks, altered breccia bodies. Blue zones indicate magnetic lows point to zones of destruction or alteration of magnetite. Encouragingly, the magnetic data is aligned with the magneto-telluric and IP surveys as disclosed to the market on January 27, 2026

Figure 2: Preliminary Bouguer Gravity from the recently completed survey at Colosseum. The red and pink zones indicate higher density rocks, whilst the green and blues indicate lower density rocks (such as sediments). The strong gravity high on the eastern side points to dense intrusive or altered bodies at depth (alkaline intrusive rocks, breccia pipe roots, or carbonatite related material). There also appears to be a sharp N-S gravity gradient that aligns with the Clark Mountain fault.

Figure 3: Preliminary Radiometrics (Total Count) from the recently completed survey at Colosseum. Dose rate represents the combined gamma radiation from potassium, thorium, and uranium in the upper soil and rock profile. Elevated total counts reflect enrichment in potassium, thorium, and uranium associated with alkaline intrusive rocks and hydrothermal alteration, highlighting structural corridors and targets prospective for gold and rare earth mineralisation.

Data Integration and Interpretation

The complete geophysical dataset, including the new infill gravity, magnetic and radiometric data together with previously completed IP and MT surveys, is currently being reviewed and integrated by Mitre Geophysics.

This integrated interpretation is focused on:

• Refining the geometry and continuity of the structures,

• Linking deep geophysical responses to mapped geology, structural features and previously identified geochemical and alteration signatures; and

• Finalising priority drill targets where multiple geophysical datasets converge.

Drilling Update

As previously advised, diamond drill rigs remain scheduled to arrive on site next week. Drill planning is progressing in parallel with the ongoing geophysical interpretation, with the objective of testing the highest-priority targets identified from the integrated dataset.

Further updates will be provided as interpretation is finalised and drilling commences.

This press release has been authorized for release by the Board of Dateline Resources Limited.

For more information, please contact:

Stephen Baghdadi
Managing Director
+61 2 9375 2353

Andrew Rowell
Corporate & Investor Relations Manager
+61 400 466 226
a.rowell@dtraux.com
www.datelineresources.com.au

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About Dateline Resources Limited

Dateline Resources Limited (ASX:DTR)(OTCQB:DTREF)(FSE:YE1) is an Australian company focused on mining and exploration in North America. The Company owns 100% of the Colosseum Gold-REE Project in California.

The Colosseum Gold Mine is located in the Walker Lane Trend in East San Bernardino County, California. On 6 June 2024, the Company announced to the ASX that the Colosseum Gold mine has a JORC-2012 compliant Mineral Resource estimate of 27.1Mt @ 1.26g/t Au for 1.1Moz. Of the total Mineral Resource, 455koz @ 1.47/t Au (41%) are classified as Measured, 281koz @1.21g/t Au (26%) as Indicated and 364koz @ 1.10g/t Au (33%) as Inferred.

On 23 May 2025, Dateline announced that updated economics for the Colosseum Gold Project generated an NPV6.5 of US$550 million and an IRR of 61% using a gold price of US$2,900/oz.

The Colosseum is located less than 10km north of the Mountain Pass Rare Earth mine. Planning has commenced on drill testing the REE potential at Colosseum.

Dateline also owns 100% of the high-grade Argos Strontium Project, also located in San Bernardino County, California. Argos is reportedly the largest strontium deposit in the U.S. with previous celestite production grading 95%+ SrSO₄.

Forward-Looking Statements

This announcement may contain "forward-looking statements" concerning Dateline Resources that are subject to risks and uncertainties. Generally, the words "will", "may", "should", "continue", "believes", "expects", "intends", "anticipates" or similar expressions identify forward-looking statements. These forward-looking statements involve risks and uncertainties that could cause actual results to differ materially from those expressed in the forward-looking statements. Many of these risks and uncertainties relate to factors that are beyond Dateline Resources' ability to control or estimate precisely, such as future market conditions, changes in regulatory environment and the behavior of other market participants. Dateline Resources cannot give any assurance that such forward-looking statements will prove to have been correct. The reader is cautioned not to place undue reliance on these forward-looking statements. Dateline Resources assumes no obligation and does not undertake any obligation to update or revise publicly any of the forward-looking statements set out herein, whether as a result of new information, future events or otherwise, except to the extent legally required.

Competent Person Statement

Sample preparation and any exploration information in this announcement is based upon work reviewed by Mr. Greg Hall who is a Chartered Professional of the Australasian Institute of Mining and Metallurgy (CP-IMM). Mr. Hall has sufficient experience that is relevant to the style of mineralization and type of deposit under consideration and to the activity which he is undertaking to qualify as a Competent Person as defined in the 2012 Edition of the "Australasian Code for Reporting Exploration Results, Mineral Resources and Ore Reserves" (JORC Code). Mr. Hall is a Non-Executive Director of Dateline Resources Limited and consents to the inclusion in the report of the matters based on this information in the form and context in which it appears.

Company Confirmations

The Company confirms it is not aware of any new information or data that materially affects the information included in the announcements dated 23 October 2024 with regard to the Colosseum MRE and 23 May 2025 with regard to Colosseum Project Economics. Similarly, the Company confirms that all material assumptions and technical parameters underpinning the estimates and the forecast financial information referred to in those previous announcements continue to apply and have not materially changed.

SOURCE: Dateline Resources Limited

View the original press release on ACCESS Newswire

FAQ

What geophysical surveys did Dateline Resources (DTREF) complete at Colosseum on February 9, 2026?

Dateline completed high‑resolution gravity, magnetic and radiometric surveys plus prior IP data integration. According to the company, surveys include 543 gravity stations on a 100 m grid and ~8.6 km² of magnetic/radiometric coverage to sharpen drill targets.

When will diamond drilling start at the Colosseum project (DTREF) and what is the drilling focus?

Diamond core drilling rigs are scheduled to arrive on site next week to begin focused testing. According to the company, drilling will target high‑priority geophysical intersections interpreted at depths of approximately 500–1,000 metres.

How will the new DTREF geophysical data change drill targeting at Colosseum?

The integrated datasets will refine geometry and continuity of deep structures to focus holes. According to the company, combining gravity, magnetics, radiometrics, IP and MT narrows targets where multiple methods converge for efficient drill testing.

What do the gravity and magnetic highs indicate at Dateline's Colosseum (DTREF) project?

Gravity and magnetic highs point to denser, magnetite‑bearing intrusives or altered breccia bodies at depth. According to the company, these anomalies align with MT and IP responses and highlight structural corridors prospective for gold and REE mineralisation.

What technical or financial challenges does DTREF note for deeper drilling at Colosseum?

Targets at ~500–1,000 metres require more technically demanding drill programs and higher costs. According to the company, the approach emphasises focused, capital‑efficient drilling but deeper testing increases operational complexity and budgetary requirements.