Cabral Gold Announces Results of Updated Prefeasibility Study on the Gold-in-Oxide Starter Operation at the Cuiú Cuiú Gold Project, Brazil
Cabral Gold Announces Results of Updated
Prefeasibility Study on the Gold-in-Oxide
Starter Operation at the Cuiú Cuiú Gold
Project, Brazil
Vancouver, British Columbia--(Newsfile Corp. - July 29, 2025) -
Cabral Gold Inc. (TSXV: CBR)
(OTCQB: CBGZF) ("Cabral" or the
"
Company
")
is pleased to announce the results of an updated
Prefeasibility Study ("Updated PFS") on the development of near-surface gold-in-oxide material at the
Cuiú Cuiú gold district in Brazil. The Updated PFS, led by Ausenco do Brasil Engenharia Ltda.
("Ausenco"), resulted in significant improvements to the amount of gold produced, mine life, Net Present
Value ("NPV") and Internal Rate of Return ("IRR") These results confirm the Cuiú Cuiú gold-in-oxide
starter project provides a high return and a low capital entry point to mine gold, with production possible
within 12 months from an investment decision.
Highlights
Financial results from this larger project are a significant improvement on the October 2024 PFS
("PFS") with the Base Case after-tax NPV
5,
rising by almost 200% from US$25.2 million to
US$73.9 million. The after-tax IRR has increased from 47% to 78% using a base case gold price
of US$2,500/oz, with payback of the initial capital in under one year
At the current Spot Gold
1
price - US$3,340/oz, the after-tax IRR increases to 139% and the after-
tax NPV
5
to US$137 million
Capital intensity has been reduced with initial capital cost essentially unchanged at US$37.7
million compared with US$37.4 million in the PFS study, including a 10% allowance on most
quantities and 20% contingency
The project has increased the annual processing capacity from 720,000 tonnes/yr to 1,000,000
tonnes/yr
Mine life has increased from 4.4 to 6.2 years at the higher annual processing rate, with strong cash
flows in the early years, resulting in the halving of investment payback from 18 months to 10
months
2
Probable Mineral Reserves have increased by 54% relative to the October 2024 PFS from a total
83,762oz to 128,908oz of gold from 6.2Mt @ 0.65 g/t gold
Life of mine gold production has increased by 56% from 72,478 ounces to 113,155 ounces at an
all-in sustaining cost ("AISC
3
") of US$1,210 / oz of gold produced
Strong evidence exists of the potential for near-term growth in the gold-in-oxide resources at Cuiú
Cuiú, particularly at the PDM and Jerimum Cima targets
The Oxide Starter Operation at Cuiú Cuiú is driven by the Company's long-term goal, which is to develop
the region's second major gold mine in the Tapajos district. This Project carries out pre-stripping for the
larger hard rock project, exposing the underlying primary gold mineralization, which reduces future waste
mining costs. It also creates an initial operating platform that makes it easier to transition into primary
ore production, and it generates significant cash flow to accelerate an aggressive and ongoing drilling
and evaluation program aimed at finding the best pathway toward the subsequent larger development of
the hard rock resources at Cuiú Cuiú.
The Company is in advanced negotiations regarding project financing with various parties, targeting a
final investment decision (FID) in Q3 2025. Based on this plan, initial gold production is targeted for the
second half of 2026.
Alan Carter, the President and CEO of Cabral Gold commented,
"We are delighted with the results from the Updated PFS on the Oxide Starter Operation at Cuiú Cuiú,
which reflects the dedication of our team and consulting advisors. All key financial metrics have
significantly improved since we issued the results of the PFS in October 2024.
While the required capital expenditures remain effectively unchanged at US$37.7 million, the after-tax
NPV has surged by nearly 200% to US$73.9 million, and the after-tax IRR has risen from 47% to 78%
over a longer project duration. The main driver behind these higher returns is the increased plant
capacity, which reduces unit costs through economies of scale and allows for a lower cut-off grade,
which results in higher Reserves. The addition of the Machichie mining area to the production
schedule offers a new source of higher grade and near surface material, enabling the project to boost
throughput and extend mine life simultaneously.
Recent drilling and trenching at Cuiú Cuiú has discovered a fifth gold-in-oxide blanket at Jerimum
Cima, which currently lacks resources due to limited drilling. This target, along with the known gold-in-
oxide resource at PDM, also not included in the Updated PFS, could offer opportunities for future
expansion or extension of the mine life for the gold-in-oxide starter operation.
The Updated PFS has checked all our boxes and delivered a significantly larger starter project with
very attractive early financial returns and quick payback, especially during a period of high gold
prices.
In parallel with developing the Oxide Starter Operation at Cuiú Cuiú, the Company is currently
undertaking an aggressive exploration drilling program aimed at pursuing the Company's main goal
of increasing the primary hard rock resource base, and testing the highest potential targets within the
Cuiú Cuiú gold district."
Overview
Cabral owns a 100% stake in the Cuiú Cuiú gold project, located in Pará State in northern Brazil,
immediately adjacent to GMining's major Tocantinzinho gold mine. Cuiú Cuiú was the largest producer
of placer gold during the 1980s Tapajós gold rush. The project area covers an entire gold district.
In 2021, the Company recognized the economic potential of several gold-in-oxide blankets created by
the weathering of the higher-grade primary gold deposits at Cuiú Cuiú. An internal desktop study verified
that these oxide resources could support the development of an initial simple, low-cost starter production
facility that could be set up in the short term based on the existing Trial Mining Licenses. Additionally, this
study indicated that such an operation could generate substantial cash flows, enabling the Company to
self-fund an aggressive and ongoing drilling program aimed at significantly expanding the global
resource estimate.
During October 2024, the Company completed a PFS-level study on a simple and low-cost starter
operation with the scope to assess short-term pathways to production that were aligned with Cabral's
financial capacity (see press release dated October 21, 2024). The PFS study resulted in robust
financial returns, including a 47% post-tax IRR and an 18-month payback at an assumed gold price of
$2,250 per ounce. However, it was recognized that with more time, significant improvements in the
project were likely, particularly the inclusion of resources from the nearby Machichie deposit, and an
increase in processing capacity to better accommodate the district's oxide resource potential.
Therefore, the Company decided to undertake additional resource drilling and metallurgical studies to
better understand the Machichie deposit, as well as engineering studies to optimize the project design
outlined in the PFS.
Mineral resources have been updated for Central and Machichie based on drilling completed in late
2024 and 2025. At MG and PDM, resources remain the same as in 2024 since there was no new drilling
or resource modeling. The project now contains a total of 13.6 Mt averaging 0.50 g/t Au in Indicated
Resources and 6.4 Mt averaging 0.34 g/t Au in Inferred Resources.
Economic Analysis
The gold-in-oxide project demonstrates very strong financial metrics across a variety of gold price
scenarios as shown in Table 1, highlighting the potentially attractive returns and quick payback period. A
comparison with the financial results of the initial PFS released in October 2024 is also included.
The after-tax NPV
5
has increased by almost 200% from US$25.2 million to US$73.9 million in the
Updated PFS. The after-tax IRR has also increased significantly from 47% to 78%. In addition, the higher
annual processing rate results in strong cashflows in the early years almost halving of investment
payback from 18 months to 10 months in the Updated PFS
4
(Figures 1 and 2).
US$M
PFS
October
2024
Low
Base Case
Mid
Spot
High
Gold Price (US$/oz)
2,250
2,250
2,500
3,000
3,340
3,500
After Tax NPV
5
25.2
54.8
73.9
112.0
137.8
149.9
After Tax IRR
47%
59%
78%
114%
139%
151%
Payback (years)
1.5
1.1
0.8
0.7
0.6
0.5
Average annual
EBITDA (First 24
months)
23.8
26.9
32.1
42.5
49.5
52.9
LOM EBITDA
79.5
127.4
154.4
208.4
245.2
262.5
LOM After Tax
Cashflow
32.8
71.5
94.4
140.2
171.3
186.0
Table1.
Key results of Updated PFS financial analysis and sensitivities to commodity prices
Figure 1 Graph showing gold produced and production costs by year
To view an enhanced version of this graphic, please visit:
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Figure 2 Monthly gold production and project payback for initial 3.5 years from Investment Decision
To view an enhanced version of this graphic, please visit:
https://images.newsfilecorp.com/files/3900/260474_530db38cc49e48ad_003full.jpg
Updated PFS - Detailed Results
The following tables (Tables 2 and 3) provide both key assumptions used to complete the financial
analysis and the primary operational statistics for the project.
Oxide Probable Reserves have increased by 54% from a total 83,762oz in the October 2024 PFS to
128,903oz of gold. Processing and heap leach capacity has similarly increased by 39% from 720,000
tonnes per annum to 1,000,000 tonnes per annum, and the waste to ore ratio has dropped from 0.93 in
the October 2024 PFS to 0.78 in the Updated PFS. Life of Mine gold production has risen by 52% from
72,478 ounces to 113,155.
All of this, whilst capex costs have essentially remained unchanged at
US$37.7 million compared with US$37.4 million in the October 2024 PFS. Life of Mine AISC costs also
essentially remain unchanged and were US$1,228 / oz in the October 2024 PFS compared with
US$1,210 / oz in the Updated PFS.
Operational Assumptions
Unit
Contained Gold in Mine Plan
oz
128,926
Mill and Heap Leach Capacity
t/annum
1,000,000
Monthly Plant Feed
tonnes
83,333
LOM Mined Grade
g/t
0.65
Strip Ratio
Waste:Ore
0.78
LOM Ore Mined
tonnes
6,179,379
LOM Material Movement
tonnes
10,993,399
Average Gold recovery
%
87.8%
Production
Mine life
Years
6.2
Gold Production (First 24 months)
oz
43,342
LOM Gold Production
oz
113,155
Average Annual Production (6.2 year mine life)
koz
18.5
Project Costs
Pre-production Capital Expenditure
US$M
37.7
Sustaining Capital Expenditure
US$M
8.02
LOM Average Site Operating Costs
US$/tonne ore
18.2
LOM Average Site Operating Costs
US$/oz
1,000
LOM Average AISC
US$/oz
1,210
Table 2. Economic analysis summary
Commercial Parameters
Unit
Exchange Rate
USD:BRL
5.7
Corporate Tax Rate
%
25.0%
Social Tax
%
9.0%
SUDAM Tax Reduction
%
75.0%
Gold Royalty Osisko Gold Royalties
%
1.0%
Gold Royalty Versamet
%
1.5%
Selling and Refining Costs
US$/oz
30.0
Table 3. Key assumptions
Resources
Overlying the primary gold mineralization at Cuiú Cuiú is an oxide zone of weathered and oxidized
intrusive saprolite material ("saprolite"). Above the saprolite, gold is present in an erosional blanket of
colluvium and other poorly consolidated sediments ("blanket"). The Updated PFS focuses on the
Indicated Resources within the saprolite and overlying blanket, where the relatively soft or poorly
consolidated material is easily excavated, and gold is highly amenable to heap leaching.
Cabral updated resource models within the oxide zone at the Central and Machichie targets based on
additional drilling of 4,755 metres at Central completed in late 2024, and 2,823 metres at Machichie
completed in 2025. Central and Machichie resources were calculated constrained within a pit shell using
a gold price of $2,600 per ounce at a 0.1 g/t cut-off grade and are shown in Table 4. Resources in the
Indicated category have increased by 26% to 13.6Mt @ 0.50 g/t gold compared with the October 2024
PFS study. Resources at MG and PDM were not updated or recalculated as there was no new drilling or
model changes, and are stated as in the 2024 43-101 Technical Report and Prefeasibility Study (see
note 4 of Table 4).
The resource estimates do not include resources in the underlying primary (hard rock) material, which
account for approximately 80% of the total resources at the Cuiú Cuiú project.
Inferred Resources are not considered as part of the Updated PFS study. Indicated and Inferred
Resources across four known deposits are shown in Table 4.
Cut-off
Grade
Inferred Resources
Indicated Resources
0.1 g/t
Tonnes
Grade
Ounces
Tonnes
Grade
Ounces
MG
3,142,921
0.223
22,508
8,857,901
0.477
135,855
Central
941,636
0.448
13,558
3,364,519
0.520
56,204
Machichie
714,188
0.540
12,403
1,334,744
0.562
24,123
PDM
1,600,000
0.430
22,100
Total
6,398,745
0.343
70,569
13,557,164
0.500
216,182
Table 4. Indicated and Inferred resources of oxide material only
Notes:
1
.
All estimates of Mineral Resources have been prepared in accordance with National Instrument 43 - 101 - Standards of Disclosure for
Mineral Projects ("NI 43-101").
2
.
The effective date is July 23, 2025.
3
.
The independent and qualified persons ("QPs") for the mineral resource estimates as defined by NI 43-101, Henrique da Silva, US
Consultants LLC (for Central resources) and Walter Dzick (P.Geo) Principal Geological Consultant of Dzick Geosconsultants (for Machichie)
4
.
MG and PDM resources are quoted from 2024 NI 43-101 Technical Report & Prefeasibility Study, effective date of October 9, 2024
5
.
Central and Machichie resources were estimated within pit shells using $2600 gold price and a 0.1 g/t Au cut-off grade.
6
.
These mineral resources are not mineral reserves.
7
.
Numbers may not add due to rounding
Mining
The Updated PFS contemplates open-pit mining using conventional methods. Initially, ore will be
sourced from three mining areas. The Moreira Gomes (MG) pit accounts for approximately 65% of the
run of mine (ROM) ore with the balance coming from the Machichie main deposit (10%) located 500m
from the ROM pad and the Central Pit (25%), located approximately 5km from the location of the ROM
pad.
Figure 3 shows the Project layout, including the mining areas (MG and Machichie) relative to the
processing plant.
Figure 3. Project layout, including the mining areas (MG and Machichie) relative to the processing
plant.
To view an enhanced version of this graphic, please visit:
https://images.newsfilecorp.com/files/3900/260474_530db38cc49e48ad_004full.jpg
Figure 4 shows the various material movement rates by month, highlighting the low level of waste
stripping during the payback period
5
.
Figure 4. Material movement schedule by month
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Pit designs were completed at a gold price of $2,250/oz, with a key focus on prioritizing the highest-
grade ore in the mine plan. This maximized IRR and margin, shortened payback, and provided strong
short-term cash flow to derisk the investment decision and improve the attractiveness to potential
investors and financiers.
The pit designs incorporated 5-meter bench heights and ramps 10 meters wide. Geotechnical stability
analysis, based on benchmarking data and field evaluation, supported inter-ramp angles of 45 degrees,
with a total pit angle ranging from 30 to 45 degrees (including ramps).
Mining will be conducted using an excavator in the overhand position, loading a fleet of 35-tonne trucks
supported by a front-end loader. The oxidized resources are found within loose, weathered blanket
material, which can be mined with an excavator, dozer, and ripper without the need for drilling and
blasting.
Mining activities will probably be outsourced to one of the many full-service contract miners operating in
Para State. Contract mining agreements will include providing the entire mining fleet, along with
operating labor and necessary maintenance services. Cabral will supply the fuel needed to run the fleet
from a mine site storage and dispensing facility.
Ore from the open pits will be delivered to a ROM pad within 200 meters from the exit of the MG pit.
Mineral Reserves
Probable Reserves for the project have been updated since the PFS and have increased by 54% from a
total 83,762oz to 128,903oz of gold. The totals are outlined in Table 5 below;
Tonnage (Kt)
Grade (g/t Au)
Ounces Au
MG
4,035
0.64
82,912
Central
1,511
0.62
29,959
Machichie
632
0.79
16,032
Total
6,178
0.65
128,903
Table 5 Probable Mineral Reserves (gold-in-oxide material only)
Notes:
1
.
CIM (2014) definitions were followed for Mineral Reserves.
2
.
Mineral Reserves have an effective date of July 23, 2025. The Qualified Person for the estimate is Bruno Yoshida Tomaselli, B.Sc.,
FAusIMM, an employee of Deswik.
3
.
Mineral Reserves stated herein are Probable Reserves confined within an optimized pit shell that uses the following parameters: gold price
including refining costs US$ 2,250/oz; mining costs US$ 4.20/t; processing costs US$ 10.00/t processed; G&A costs US$ 1.5 M/a; process
recovery of 75% at Central and 85% at Machichie and MG; mining dilution of 5% at MG and Central and 10% at Machichie; ore recovery of
95%; pit overall slope angles that range from 30 - 45°.
4
.
Tonnages and grades have been rounded in accordance with reporting guidelines. Totals may not sum due to rounding.
Metallurgical results
Metallurgical test work was completed at Kappes Cassiday and Associates (KCA) in Reno, NV, on a
total of ten oxide material samples from the MG, Central, and Machichie deposits. KCA performed a
series of tests on each composite, including coarse and fine milled bottle roll leach tests, compacted
permeability tests, and column leach tests. Gold extractions in the bottle-roll leach tests generally
exceeded 90%, with a maximum recovery of 98% achieved after 336 hours of leaching.
Column leach tests were performed using material crushed to 100% passing 50 millimeters for MG and
Central, and 25 mm for Machichie. The material was agglomerated with 15 to 20 kg/t of cement. To
replicate the height of the proposed leach pads, the MG and Central material was loaded into 5-meter-
tall, 8-inch (203 mm) diameter columns, which were leached for 68 to 112 days with a cyanide solution.
The Machichie material was loaded into 2.4-meter-tall, 6-inch (150 mm) diameter columns, which were
leached with cyanide for 22 to 35 days.
In general, gold recoveries within columns were excellent, with most of the final leach extractions
achieved within the first few weeks of the cycle.
Recent testwork, which focused on the Machichie ore,
returned recoveries of 91% in the saprolite and 96% in the blanket sediments. A blended estimate
recovery of 88% was used for Machichie ore in the Updated PFS. The recoveries for Central (87%) and
MG (88%) were consistent with the assumptions used in the October 2024 PFS.
Saprolite at MG and Machichie is highly oxidized, resulting in high porosity and very good gold
recoveries, especially when agglomerated. Central saprolite is comparatively coarser grained with less
natural leaching, leading to slightly lower recoveries. Blanket material at all deposits shows variability in
gold recoveries but consistently yields very high recoveries due to the high level of oxidation in the near-
surface environment.
Based on these test results and our understanding of the ore types, Ausenco has determined the
following heap leach recoveries for the different ore types based on a 60-day leach cycle, using on/off
operation.
Processing
The Cuiú Cuiú processing facility has been designed with a capacity of 3,000 tpd. This is a 50%
increase from the 2,000 tpd contemplated in the PFS of October 2024.
The process plant will include a mineral sizer (MMD Sizer) fed from a ROM pad, producing an ore
stream with an 80% passing size of 50 mm (2"). The crusher discharge will be agglomerated using
cement and barren leach solution, then transported by portable conveyors to the on/off heap leach pads.
There will be four leach pads, each with a designed capacity of 83,333 tonnes at a stacked ore height of
5 meters. One or two pads will be leaching at any given time, with an irrigation rate of 12 L/h/m
2
. Pads
not currently leaching will be in the process of being prepared or cleaned of spent ore. Although the leach
cycles are assumed to last 60 days, some of the softer blanket material may be leached in a shorter time
without significantly affecting process recovery.
Pregnant leach solution (PLS) will be pumped to the carbon-in-column (CIC) circuit at an average flow
rate of 215 m³/h, targeting a loaded carbon Au grade of 2,500 g/t. This will be processed in a 2.0-tonne
capacity Adsorption/Desorption and Recovery (ADR) plant. The ADR plant will include an acid wash
column, elution column, carbon regeneration kiln, electrowinning cell, sludge filter press, sludge drying
oven, and smelting furnace.
Once the leach cycle is complete, the pads will be completely rinsed during a 14-day period, and if
required, the solution will be detoxified using lime and hydrogen peroxide prior to initiating the rinsing
process. The gold recovery flowsheet for the project is shown in Figure 5.