TCO.V · 2025-07-21 12:00:00

Transatlantic Samples 3.1% Cu over 0.3 metres at Monitor Project - Anvil Prospect

Drill Results Sampling & Geoscience Results

Transatlantic Mining Corp. | Suite 400 | 837 West Hastings Street | Vancouver | Canada

V6C 3N6 T 604-630 7296 | F 604-357 1139| www.transatlanticminingcorp.com

Transatlantic Samples 3.1% Cu over 0.3 metres at Monitor

Project - Anvil Prospect

Vancouver, B.C. July 21, 2025 - Transatlantic Mining Corp. (the “Company”) ( TCO:TSX.V) is

pleased to provide an update on its exploration activities at the Anvil prospect, key target

within the larger Monitor Copper -Gold Project. The project is located approximately 8

kilometers south of Taft, Idaho, USA and continues to demonstrate prospectivity.

Highlights of the Exploration Program:

● High-Grade Underground samples at Anvil: An outcrop sample returned 3.1% copper

(Cu) over 0.3 metres

● Anvil Prospect Potential: Recent underground samples at Anvil indicate multiple

copper fissure veins within a complex system that are anomalous in copper and

support larger Copper Fissure System in the district.

"Samples underground and confirmation of 2 orientations with copper mineralisation are

encouraging for further follow up ,” said Bernie Sostak, CEO of Transatlantic Mining. This

supports multiple high grade copper mineralisation veins in the region. We look forward to

uncovering more copper in the district with updated geophysical techniques along strike and

down dip."

Geology and Mineralization

At the Anvil prospect, copper mineralization is found within steeply dipping fissure veins that

form along second-order structures within a prominent shear zone, trending approximately

N40W to N70W. These veins, typically can be up to 1.8 metres wide, are characteristic of the

broader Coeur d’Alene mining district. In this eastern and southeastern part of the district,

where the Monitor Project is situated, veins are typically copper -rich with reduced silver,

lead, and zinc content, suggesting formation under higher-temperature conditions or closer

proximity to the hydrothermal source. These copper -rich veins are generally less than 5

meters wide, extend to significant depths, and primarily contain chalcopyrite, pyrite, calcite,

siderite, and quartz. Hydroth ermal alteration, notably pervasive siderite zoning and

bleaching, is a defining characteristic of the mineralized zones, with disseminated siderite

sometimes extending hundreds of meters into the wall rocks.

Transatlantic Mining Corp. | Suite 400 | 837 West Hastings Street | Vancouver | Canada

V6C 3N6 T 604-630 7296 | F 604-357 1139| www.transatlanticminingcorp.com

Exploration Results

Building on this geological understanding, the Company conducted a systematic exploration

program, implementing industry best practices to confirm the property's geological and

mineralogical characteristics.

Initial underground sampling at the Anvil prospect yielded encouraging copper results. An

underground adit returned samples up to 3.1% Cu over 0.3 metres (see Figure 1,2). ( *See

also historical reports)

The historical workings at the Anvil prospect were explored, mapped, and sampled. These

workings were developed along a northeast -trending mineralized structure. The workings

and this northeast-trending structure intersect a distinct northwest-trending structure. All of

these structures were sampled as part of the program. Samples collected were subsequently

sent to Christofferson Labs, LLC. in Smelterville, Idaho, USA for analysis of gold and then to

American Analytical Laboratories in Osburn, Idaho for an ICP analysis.

Transatlantic Mining Corp. | Suite 400 | 837 West Hastings Street | Vancouver | Canada

V6C 3N6 T 604-630 7296 | F 604-357 1139| www.transatlanticminingcorp.com

Figure 1: Map of the Big Elk Prospect, a subset of the Monitor Project

Figure 2: Map of the Anvil Prospect, an underground subset of the Monitor Project (Table 1)

Overall, the Company's exploration efforts confirmed the strike and dip of the vein mined

along the Big Elk workings. Surface samples indicate the veins contain copper mineralization.

Furthermore, through mapping and sampling of the Anvil working, the Comp any has

identified additional veins within the claim block. Both the Big Elk and Anvil prospects

represent historical workings on fissure veins within the larger shear zone, confirming the

presence of multiple veins within the shear zone that encompasses the entire project.

Sampling, Analysis, and Quality Assurance/Quality Control (QA/QC)

All samples, are those from chip samples underground in the Anvil Adit across strike of the

vein. The samples were up to 5 kilograms and were sent to Christofferson Labs, LLC in

Smelterville, Idaho, USA for gold analysis. Subsequent ICP analysis was performed at

American Analytical Laboratories in Osburn, ID. All sampling results for the Anvil prospect

Transatlantic Mining Corp. | Suite 400 | 837 West Hastings Street | Vancouver | Canada

V6C 3N6 T 604-630 7296 | F 604-357 1139| www.transatlanticminingcorp.com

are detailed in Table 1. All analytical procedures adhered to industry-standard protocols, and

results have passed internal QA/QC checks.

Table 1: Sampling across Anvil Prospect Underground Vein

Sample ID Sample

Type

From

(m)

Length

(m)

True

Width (m) Cu % Au g/t Ag g/t Description

MON_ 241016_01 Chip 0 0.4 0.4 0.4 0.1 0.20 2.72 Siderite vein dip 50 degrees

MON_ 241016_02 Chip 0 0.4 0.4 0.4 0.1 0.75 3.40 Siderite vein dip 50 degrees

MON_ 241016_03 Chip 0 0.3 0.3 0.3 1.5 1.05 11.90 Copper mineralised vein dip 80

degrees

MON_ 241016_04 Chip 0 0.3 0.3 0.3 3.1 0.20 1.70 Copper mineralised vein dip 80

degrees

MON_ 241016_05 Chip 0 0.3 0.3 0.3 0.7 0.10 2.72 Copper mineralised vein dip 80

degrees

*Underground rockchip samples, such as those described herein, are selective by nature and are not necessarily indicative of the

total average grade of mineralisation

Transatlantic Mining Corp. | Suite 400 | 837 West Hastings Street | Vancouver | Canada

V6C 3N6 T 604-630 7296 | F 604-357 1139| www.transatlanticminingcorp.com