Potential of Antinomy & Copper at Black Star

London, New York, 5 October 2026 - London BTC Company Limited (“Company”) (BTC: LSE, VINZF: OTCQB), the London Stock Exchange main market-listed company, is pleased to announce that initial results have been returned by on-site pXRF analysis for antimony and copper from its latest exploration programme at the Black Star Gold - Critical Minerals Project (“Black Star” or the “Project”) in Pershing County, Nevada.

Hewie Rattray, CEO of London BTC, states:

“Black Star was originally staked for its high-grade gold and silver potential, so identifying antimony within our own claims and high-grade copper is a particularly encouraging development.

What is of particular interest is not simply an isolated antimony reading, but that the initial on-site pXRF analysis has indicated the presence of antimony at both ends of an approximately 2.5 km corridor, alongside copper, bismuth and silver. The results indicate a multi-element signature that appears consistent with the historical mineral occurrence immediately to the south of the Project.

Antimony is designated as a critical mineral in the United States, and the potential for the Project to host gold and silver mineralisation alongside a strategically important critical mineral further increases our interest in the Project.

These are preliminary field readings and laboratory assays remain the important next step. Those samples are now with MSALABS, while our exploration programme continues across the wider Nevada portfolio.”

Key Points

• Maiden exploration completed at Black Star, with 69 rock chip samples collected along the 2.5 km corridor between the Western and Eastern targets.
• Antimony identified by pXRF with readings of up to 0.44% Sb at the Eastern Target (BTCRK1014) and 0.17% Sb and 0.15% Sb from the Western Target (BTCRK1032 and 33).
• Copper-antimony-bismuth-silver association with copper readings of up to 30.0% Cu, bismuth up to 0.73% Bi and silver readings up to 811 ppm (grams/tonne) Ag. While pXRF is indicative, this multi-element signature closely resembles the historical 1985 sample located 120 m south of the claims (>1% Sb, 2% Cu, 700 ppm Ag, 1,000 ppm Bi).
• pXRF does not determine gold, and silver readings are qualitative. Laboratory assays will be reported once received, subject to QAQC and Competent Person review.
• Previous due diligence sampling at Black Star returned up to 16.23 g/t gold and 50.5 g/t silver, confirmed through PhotonAssay™ and Fire Assay QAQC.
• Samples submitted to MSALABS in Nevada for gold and silver by PhotonAssay™, to be followed by sodium peroxide fusion for full multi-element geochemistry, including antimony, tungsten and copper.
• Field team now moving to Amonett-Frank (up to 143.1 g/t gold and 88.3 g/t silver), to be followed by Huntington-Whitman.

David Lenigas, London BTC Company's Chairman, comments;

"Black Star was staked for its high-grade gold, and our first field readings have now identified antimony within our own claims, not just at the historical sample site next door. Seeing antimony, copper, bismuth and silver together at both ends of the 2.5 km corridor is exactly what we hoped for when we flagged the antimony potential at this site earlier this year in August.

Antimony is designated as a critical mineral in the United States, and the potential for a Nevada gold-silver project which may also carry an antimony credit makes the Project an attractive proposition for the Company, subject to further lab testing. We look forward to the assays, as the team moves on to Amonett-Frank, where initial testing has reported results of 143.1 g/t gold, followed by Huntington-Whitman."

Figure 1: Black Star Project, preliminary pXRF results against existing Photon AssayTM samples

Black Star Exploration Programme

The Black Star Project comprises 36 unpatented mineral claims covering 744 acres (3 km²) in the Trengo District of Pershing County, northern Nevada. The Project covers a contact between metavolcanic rocks and granodiorite, targeted historically by shafts, adits and prospect pits developed on quartz veins, with limited follow-up exploration since the 1980s. Previous due diligence sampling defined two high-grade gold-silver target areas, the Western and Eastern targets, separated by approximately 2.5 km of underexplored ground.

The maiden programme was designed to extend sampling along the corridor between the two targets, to test the historical workings for antimony and associated pathfinder elements, and to follow up the Company's announcement of 14 August 2026, which identified historical antimony mineralisation grading greater than 1% Sb approximately 120 m south of the claims. A total of 69 rock chip samples were collected from historical workings and outcrop:

• Eastern Target: 28 samples from historical workings across quartz and quartz-calcite veins, including an approximately 20 m wide zone of quartz veining within the host rock.
• South-East: 3 samples from historical costeans exposing iron-oxide and manganese-altered skarn-type material.
• Corridor: 15 samples from sub-cropping quartz veins with iron-oxide and goethite veining, several with trace malachite, between the two targets.
• Western Target: 23 samples from across historical shafts and from surrounding quartz veins, including samples with visible chalcopyrite and malachite.

Field observations recorded iron-oxide cubic ex-sulphides (interpreted as oxidised pyrite) at both targets, visible chalcopyrite and malachite at the Western Target shafts, and possible galena in shafts. The skarn-type material recorded in the south-east is consistent with metasomatism along the intrusive contact and with the intrusion-related model previously reported for Black Star. This interpretation is conceptual and will be tested through mapping, assays and technical assessment by Dahrouge Geological Consulting.

pXRF Results

All 69 samples were analysed in the field by pXRF. Antimony was detected above the instrument limit of detection in 35 samples, with elevated readings at both the Western and Eastern targets. Selected results are presented in Table 1.

Table 1: pXRF results, Black Star rock chip samples, <LOD: below instrument limit of detection.

*pXRF is less reliable for silver; silver values are qualitative only. pXRF does not determine gold. Readings were taken on unprepared samples and are preliminary and indicative only.

Each sample was analysed with a handheld pXRF analyser (Vanta M-Series) in Geochem (3-beam) mode, with a 15-second count per beam. Three readings were taken per sample across the full range of material collected, and the maximum reading for each element is reported. Reported values are point measurements on unprepared rock surfaces and are strongly influenced by the distribution of individual mineral grains. As such, samples should be treated as an indication of the elements present rather than as grades.

Antimony at Black Star

On 14 August 2026 the Company reported that historical sample 2930, collected by the Nevada Bureau of Mines and Geology in 1985 approximately 120 m south of the Black Star claims, returned greater than 10,000 ppm Sb (above the upper limit of the analytical method), together with 2% Cu, 700 ppm Ag, 1,000 ppm As, 1,000 ppm Bi and 700 ppm Pb. Antimony was not included in the analytical suite for the Company's due diligence sampling, which was assayed for gold and silver only.

The September pXRF readings show the same copper, antimony, bismuth, silver and arsenic association within the Project at both the Western and Eastern targets. At the Eastern Target, BTCRK1014 returned readings of 0.44% Sb, 2.3% Cu and 0.34% Bi. At the Western Target, material from the historical shaft returned readings of up to 0.17% Sb and 30% Cu. The recurrence of this signature approximately 2.8 km apart suggests that antimony may be associated with the broader Black Star mineral system rather than confined to a single occurrence. This interpretation is conceptual and requires confirmation by laboratory assays, mapping and Dahrouge Geological Consulting’s technical assessment planned for mid-October.

Antimony is designated as a critical mineral by the United States Government, which remains substantially import-reliant for the commodity (USGS, 2025). Black Star remains a gold-silver exploration project, and any antimony would be assessed as a potential by-product credit alongside gold and silver.

Previous Due Diligence Results

Due diligence sampling by Schiehallion Consulting in June 2026 comprised 19 rock chip samples, submitted for PhotonAssay™ at MSALABS, with QAQC by fire assay. Fire assay results were comparable to PhotonAssay™ results. Highlights are below.

Table 2: Black Star due diligence rock chip highlights

Assay Programme

All 69 Black Star samples have been submitted to MSALABS in Nevada. Gold and silver will be determined by PhotonAssay™, which offers a short laboratory turnaround. The same samples will then undergo sodium peroxide fusion with ICP-MS/OES finish for full multi-element geochemistry, including antimony, tungsten, copper and bismuth, with over-limit samples to be re-analysed by ore-grade methods. Multi-element results carry a longer laboratory turnaround and are expected to follow the gold and silver results by several weeks.

All results will be released once received, subject to QAQC and Competent Person review.

Next Steps

• Reporting of gold and silver PhotonAssay™ results from the 69 Black Star samples, and from the 78 samples collected at Teep.
• Reporting of multi-element results, including antimony and tungsten, expected from late October 2026.
• Maiden exploration at Amonett-Frank, followed by Huntington-Whitman.
• Geological assessment by Dahrouge Geological Consulting from October 2026, covering structural setting, alteration and controls on mineralisation.
• Continued due diligence and staking over the Company's pipeline of new gold, silver, antimony and tungsten targets across Nevada, Arizona and Texas.

Programme Timetable

Indicative programme timetable, Phase Two, August to December 2026

Figure 2: London BTC Company existing gold-silver project portfolio, US State of Nevada

References

U.S. Geological Survey. Mineral Commodity Summaries 2025. Reston, VA: U.S. Department of the Interior, 2025.

U.S. Geological Survey. "Dottie Group." Mineral Resources Data System (MRDS), no. 10222757.

U.S. Geological Survey. "Heather Arising." Mineral Resources Data System (MRDS), no. 10198567.

U.S. Geological Survey. "J.D." Mineral Resources Data System (MRDS), no. 10150096.

London BTC Company Limited, “Staking of the Huntington-Whitman Gold Project”, RNS, 9 June 2026, London Stock Exchange.

London BTC Company Limited, “Second Gold Project Staked”, RNS, 11 June 2026, London Stock Exchange.

London BTC Company Limited, “37 g/t Gold and 1,332 g/t Silver in Nevada”, RNS, 18 June 2026, London Stock Exchange.

London BTC Company Limited, “Gold Discovery In Nevada, USA”, RNS, 15 July 2026, London Stock Exchange.

London BTC Company Limited, “Gold Assays Return up to 143.1 g/t in Nevada USA”, RNS, 5 August 2026, London Stock Exchange.

London BTC Company Limited, “Teep Gold Project in Nevada now Extends to 3.5km”, RNS, 11 June 2026, London Stock Exchange.