Quantum Updates Resources at Sagebrush Following Increase to Working Interest

Quantum Helium Limited (AIM: QHE), advancing helium, hydrogen and hydrocarbon projects in the USA, provides updated net resource figures for the Sagebrush Helium Project in Colorado following the increase in its working interest from 82.5% to 90%, as announced on 11 December 2025.

The underlying gross volumes remain unchanged from the Sproule ERCE independent evaluation announced on 18 September 2025 under SPE PRMS Standard (*), with Quantum's higher working interest now reflected in the revised net figures.

Updated Net Prospective Resources - Sagebrush

(Net After 16.67% Royalty, Net to Quantum at 90% WI)

Source of gross resource data: Sproule Sagebrush Resource Evaluation Report (18 September 2025).

Helium (MMscf)


Estimate	Gross Helium	Net After Royalty	Net to Quantum (90% WI)
1U	80	67	60
2U	134	112	101
3U	269	224	202

Hydrocarbon Gas (MMscf)


Estimate	Gross Hydrocarbon Gas	Net After Royalty	Net to Quantum (90% WI)
1U	661	551	496
2U	1,101	917	825
3U	2,218	1,848	1,663

CO₂ (MMscf)


Estimate	Gross CO₂	Net After Royalty	Net to Quantum (90% WI)
1U	1,161	968	871
2U	1,964	1,637	1,473
3U	3,899	3,249	2,924

Total Raw Gas (MMscf)


Estimate	Gross Total Gas	Net After Royalty	Net to Quantum (90% WI)
1U	2,906	2,422	2,180
2U	4,842	4,034	3,631
3U	9,760	8,133	7,320

Sagebrush Seismic Acquisition Update

The high-resolution 3D seismic programme at Sagebrush continues to progress very well. Field crews have maintained strong productivity throughout the past week, with data recording and receiver retrieval proceeding smoothly, and overall acquisition now well advanced.

Based on current progress, the Company expects the seismic survey to be substantially completed by the middle of this week, after which the dataset will move into processing. Initial processed outputs remain on track for delivery in January.

Qualified Person Statement

The information contained in this announcement has been reviewed and approved by Jeff Aldrich, Principal Geoscientist P.G., L.P.G, Sproule ERCE. Certified Petroleum Geologist (CPG), American Association of Petroleum Geologists (AAPG)

Note: (*) Resources have been estimated by Sproule ERCE using the reserve and resource estimation guidelines outlined by the Petroleum Resources Management System (PRMS), as revised June 2018. Helium and Carbon Dioxide gas has been evaluated as a non-hydrocarbon gases using the principles of the SPE PRMS as allowed by the SPE August 2022 statement on the "Extension of PRMS Principles to Non-Hydrocarbon/Non-Traditional Situations".

Enquiries:


Quantum Helium Limited Carl Dumbrell Chairman	NOMAD and Joint Broker SP Angel Corporate Finance LLP Stuart Gledhill / Richard Hail / Adam Cowl +44 (0) 20 3470 0470
Brand Communications Alan Green Tel: +44 (0) 7976 431608	Joint Broker CMC Markets UK Plc Douglas Crippen +44 (0) 020 3003 8632

Updates on the Company's activities are regularly posted on its website: www.quantum-helium.com

Notes to editors

Quantum (AIM: QHE) is a helium, hydrogen and hydrocarbon exploration, development, and production company with projects in the US and Australia. Quantum's strategic objectives remain consistent: to identify opportunities which will provide operating cash flow and have development upside, in conjunction with progressing exploration. The Company has several projects in the US, in addition to royalty interests in Australia.

Glossary


Term	Definition
1U / Low Estimate	At least a 90% probability that the quantities recovered will equal or exceed this estimate.
2U / Best Estimate	At least a 50% probability that the quantities recovered will equal or exceed this estimate. Often considered the "most likely" case.
3U / High Estimate	At least a 10% probability that the quantities recovered will equal or exceed this estimate. Represents upside potential.
Contingent Resource	Those quantities of petroleum estimated, as of a given date, to be potentially recoverable from known accumulations by application of development projects, but which are not currently considered to be commercially recoverable owing to one or more contingencies.
MMscf	Million standard cubic feet of gas, measured at standard conditions of temperature and pressure.
Mscf	Thousand standard cubic feet of gas, measured at standard conditions of temperature and pressure.
Prospective Resource	Those quantities of petroleum estimated, as of a given date, to be potentially recoverable from undiscovered accumulations by application of future development projects.

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