Orosur Mining Inc - Pepas moving into Mineral Resource Estimate drilling within wider exploration programme
Orosur Mining Inc - Pepas moving into Mineral Resource Estimate
drilling within wider exploration programme
• Orosur moving to parallel streams - exploration and resource
drilling.
• Rig now infill drilling Pepas as precursor to MRE.
• Decision based on positive conceptual studies.
• Geological consultants on site to develop required geological
models for both Pepas and APTA.
London, July 14th 2025 . Orosur Mining Inc. ("Orosur" or the
"Company") (TSXV/AIM:OMI), is pleased to announce an update on the
progress of exploration activities at the Company's flagship Anzá Project
("Project") in Colombia.
The Company announces that it has taken the formal decision to begin a work
program that, if successful, is designed to allow a Mineral Resource Estimate
(MRE) to be calculated at its Pepas gold prospect, within the Anzá gold project
area in Colombia.
This decision has been taken on the basis of external conceptual studies that
suggest the location and physical characteristics of the gold mineralisation so
far defined at Pepas, in the context of record high gold prices, may offer
potential nearer term production opportunities.
This decision does not stop exploration at Pepas, the wider Anzá project or the
Company's El Pantano project in Argentina. The Company is confident that both
exploration and resource definition streams can be run in parallel within the
limits of the Company's financial, human and technical resources. The primary
impact is that the single drill rig currently employed on the Project has been
diverted toward infill drilling within the current boundary of known high grade
gold mineralisation at Pepas. During this time, geological studies and additional
surface field work will be undertaken at Pepas and other prospects so that
targets are ready for the rig to move back to regional exploration once the
resource infill is completed.
Colombia - ANZÁ Project
The Anzá Project is now 100% owned by the Company following completion of
a Share Purchase Agreement ("SPA"), announced 28 th November 2024,
whereby the Company purchased all of the shares of its previous JV partner;
Minera Monte Aguila ("MMA").
The Project, which is located 50km west of Medellin, is easily accessible and
boasts excellent infrastructure including water, power and communications as
well as a large exploration camp.
The Project sits within the prolific mid-Cauca belt, Colombia's primary gold belt,
and is located along strike between several world class gold/copper deposits
including Buritica, Quebradona and Guayabales/Marmato (Figure 1).
From September 2018 to November 2024, the Anzá Project was under the
control of its previous JV partner MMA, itself a 50/50 venture between the
world's two largest gold miners, Agnico Eagle Mines and Newmont Mining.
Figure 1. Mid-Cauca Belt
Prospects
The Company is currently focussed on three prospects within the Anzá Project
- Pepas, APTA and El Cedro. All three prospects are within the same granted
exploration title that is broken into two non-contiguous pieces (Figure 2).
Drilling is currently being undertaken at the Pepas prospect in the northern
extent of the Anzá Project (pre-acquisition) over 10km north of the central base
camp at APTA. In parallel, mapping and sampling is being undertaken over the
El Cedro porphyry system in the south of the project area.
Pepas and North Pepas Prospects
The Pepas prospect is in the far north of the Anzá project and was discovered
by the Company's previous JV partners, MMA, in late 2021 by BLEG sampling
and geological mapping, followed by 11 diamond drill holes in 2022 (PEP001
to PEP011).
After completion of the transaction to buy MMA, the Company restarted drilling
at Pepas in late-November 2024.
Drilling commenced with hole PEP012, which was positioned to confirm
previous high-grade results in holes PEP001, PEP005 and PEP007 drilled in
2022.
Since reassuming control of the Project in December 2024, the Company has
released assay results from 26 holes (PEP012 to PEP037), most of which were
concentrated in and around the central core of near -surface high-grade gold
mineralisation.
Figure 3. Plan of holes, core Pepas zone.
This small, but thick and high-grade zone of mineralisation has developed very
quickly since the Company reassumed control, and while the surrounding areas
remain largely unexplored, the Company feels that what has thus far been
defined is worthy of econom ic study, especially in the current gold price
environment.
Geological Modelling and Economic Studies
As previously announced, encouraged by the exceptional results at the Pepas
prospect, the Company has begun the process of geological modelling and
preliminary economic assessment at Pepas.
The characteristics of Pepas that encouraged the Company to begin the
process of conceptual study are its high grade, surficial nature, thickness,
availability of power to site, proximity to the main regional highway without
having to pass through villages, and the existence of numerous nearby mines
and processing facilities that might offer the opportunity for third party toll
treating.
The Company carried out its own internal geological resource models and high-
level concept studies, the results of which the Company felt were sufficiently
positive that it then engaged an external mineral consulting firm to model
preliminary pit shells in order to assess if Pepas warranted further study. The
results of this high -level conceptual study were positive and have led to the
Company making the formal decision to examine Pepas in more detail, with the
ultimate objective of determining if a near te rm production option can be
developed at Pepas in its current form.
Resource Drilling
The first stage in this process is the creation of a Mineral Resource Estimate
(MRE) at Pepas, that can then be used as the basis for later economic
evaluation. To that end, one of the outputs of recent work was the development
of an infill drilling plan that, if successful, could be sufficient to allow an MRE to
be calculated. Ultimately, the amount of drilling required to develop an MRE
will be subject to results and may be modified during the infill drilling
process. However, at this preliminary stage, the Company feels that between
1,500m and 2,000m of additional drilling should be sufficient.
The single drill rig that the Company has on site at Anzá, has been moved back
to infill drilling at Pepas. On current production rates, it is expected that this plan
should be completed in November 2025, assuming no major modifications
being necessary following analysis of results.
Once completed, subject to results and the availability of consultants for the
required QAQC visits to the Project, the Company is targeting December 2025
for completion of this process and publishing of an MRE at Pepas.
Geological Assessment
In addition to drilling information, an MRE, in accordance with NI43 -101, also
requires a robust and defensible geological model to underpin the interpolation
and extrapolation of information between and beyond drill holes. To date, the
Company has not been able to develop such a model at Pepas due to the speed
with which drilling and results have progressed since the Company reassumed
control in December 2024. Drilling thus far has focussed on defining a shallow,
potentially economic orebody, with Compan y drilling since December 2024
limited to some 80m vertical depth.
To satisfy this MRE requirement, an external geological consultant, specialising
in structural geology and metamorphic petrology, has travelled to the Anzá
project to spend several weeks with Company geological staff examining all of
the historical drillin g undertaken at Pepas and APTA since the Company
acquired the project in late 2014.
The objectives of this visit and program are three-fold:
1. Develop a geological model to underpin a potential MRE at Pepas.
2. Understand the wider Pepas epithermal system, and in particular, define
the litho-structural controls upon the exceptionally high-grade mineralised
zone at Pepas and plan a targeting methodology to guide exploration
toward finding repetitions and source feeder zones.
3. Develop a geological model to explain the controls upon the very high -
grade mineralisation historically defined at the APTA deposit at Anzá to
facilitate an MRE being defined at APTA.
APTA
The APTA deposit lies in the centre of the Anzá project and has been the
subject of most exploration activity on the project, with some 38,000 metres of
drilling having been completed.
APTA is thought to be a hybrid mineralised system with an earlier VMS system
being overprinted by later epithermal events. However, most historical work at
APTA has been undertaken either by the Company's predecessor (Waymar
Resources) or by its previous JV partner (MMA), both of which focussed on
drilling, with minimal geological interpretation.
Numerous thick, high -grade gold intersections have been recorded at APTA
(Table 2), that have defined several distinct high-grade ore pods, separated by
lower grade halo material. Internal and external modelling have suggested that
a NI43-101 MRE could pot entially be possible at APTA as it stands now, but
with limited understanding of the controls upon these high -grade pods, any
MRE would be conservative. Therefore, one of the objectives of the current
geological site visit by, is to work with internal geol ogical teams to better
understand these high -grade zones and so allow any future MRE to better
reflect the impact of these zones.
An outcome of this geological study may be the recommendation for more
drilling to underpin this new geological model, and as such any move toward an
MRE will be dependent upon outcomes of this study and any subsequent work
programs.
Wider Exploration Work
As noted, moving Pepas toward an MRE is not a fundamental shift in the
Company's direction, but rather a temporary adjustment to drilling priorities for
several months. While this process is underway, field mapping and sampling
will continue at other pros pects in readiness for the rig moving back to
exploration once the infill is complete.
Drilling at Pepas North and elsewhere in the Pepas region has indicated that
Pepas is part of a much larger epithermal system consisting of wider scale low
grade halo mineralisation and at least one discrete high-grade pod. One stated
outcome of the curren t geological visit is to derive an understanding of the
controls upon the high-grade zones, and as importantly, the likely source feeder
zones. The outcome of this study will likely be a work program of surface
sampling and mapping that may provide drill targets around Pepas.
As announced, soil sampling at the El Cedro porphyry system at Anzá has been
delayed due to seasonal rains and road access issues. Sampling will
recommence once access has been reestablished.
The Company's early stage El Pantano gold exploration project in Argentina is
drill ready. The Company is currently negotiating with local drill companies and
examining options for camps, with a view to commencing drilling before the end
of the calendar year.
Best drill intersections at Pepas - previously announced
26 holes have been drilled at Pepas since the MMA transaction in November
2024.
Assay results are tabulated below.
Hole Number From (m) To (m) Interval
(m) Au (g/t)
PEP001 0 150 150 3
PEP005 0 36.85 36.85 2.13
PEP007 0 80.3 80.3 3.05
PEP012 0 66.75 66.75 5.64
PEP013 0 77.30 77.30 7.68
PEP014 0 75.1 75.1 5.58
PEP015 23.5 63.7 40.2 3.75
PEP016 61.6 105.3 43.7 3.13
PEP017 56.1 96.3 40.2 2.06
PEP018 0 54.1 54.1 6.01
PEP019 0 44.3 44.3 1.63
PEP020 0 54.65 54.65 1.94
PEP021 0 107.05 107.05 6.22
PEP022 0 76.3 76.3 7.24
PEP023 0 15 15 1.7
PEP024 9.24 15.6 6.35 1.99
PEP025 0 10.1 10.1 1.45
16.5 79 62.5 5.4
PEP026 0 14.8 14.8 0.57
43.6 72 28.4 2.52
PEP027 1 80.15 79.15 2.0
PEP028 29.5 60.85 31.35 1.61
PEP029 0 30.7 30.7 0.31
PEP030 0 77.9 77.9 0.32
115.6 122.6 7 0.31
PEP031B 28.15 41.1 12.95 0.73
74.1 95.9 20.8 0.3
PEP032 0 92 92 1.68
PEP033 0 21.3 21.3 5.88
PEP034 36 95 59 10.15
PEP035 0 11.4 11.4 2.71
PEP036B 0 40.45 40.45 0.62
PEP037 0 3 3 0.65
97.4 111.7 14.3 0.32
Table 1. Best drill intersections, Pepas.
Best drill intersections at APTA - previously announced.
Hole Number From (m) To (m) Interval
(m) Au (g/t)
MAP011 213 219 6 18.26
MAP020 145 186 41 18.26
MAP021 224 242 18 14.14
MAP033 157 179 22 10.42
MAP036 198 227 29 3.88
MAP038 172 212 40 14.09
MAP048 181 195 14 40.37
MAP054 41 59 18 2.96
97 110 13 4.36
144 149 5 17.76
MAP055 177 190 13 4.36
MAP060 217 240 23 5
MAP062 217 233 12 5.28