Oroco Resource Corporation. (“
Oroco” or the
“
Company”) (TSXV: OCO; OTCQB: ORRCF, BF: OR6) is
pleased to announce a Preliminary Economic Assessment
(“
PEA”) and updated Mineral Resource Estimate
(“
MRE”) for the North Zone and South Zone of its
Santo Tomas Porphyry Copper Project (“
Santo Tomas”
or the “
Project”) in Sinaloa State, Mexico. The
PEA results support a staged open pit mine and processing plant
starting at 60,000 tonnes per day (“
t/d”) in year
1 of production, expanding to 120,000 t/d in year 2 over a
20.1-year Life of Mine (“
LOM”). Production is
preceded by two years of construction and pre-stripping. The PEA
has been prepared by Ausenco Engineering USA South Inc.
(“
Ausenco”). The updated MRE and geologic model
were prepared by SRK Consulting (US), Inc. of Denver, Colorado and
SRK Consulting (Canada), Vancouver, BC (“
SRK”).
SRK (Canada) was responsible for geotechnical modeling. The mine
planning and mine costs components of the PEA were prepared by
Mining Plus Canada Consulting Ltd. (“
Mining
Plus”).
Highlights of the Santo Tomas PEA
include:
- US$2.33 billion pre-tax NPV (8%) and US$1.24 billion after-tax
NPV (8%)
- 23.0% pre-tax IRR; 17.3% after-tax IRR.
- Total LOM payable copper production of 4,749 M lb.
- Pre-tax payback of 4.1 years; after-tax payback of 5.0 years
from first concentrate production.
- Initial capital costs estimated at US$1,339.9 million;
sustaining and expansion capital costs estimated at US$1,134.5
million.
- Average annual LOM C1 Cash Cost of US$1.66/lb Cu on by-product
basis.
- An ultimate pit design constrained resource of 388 Mt of
Indicated and 460 Mt of Inferred material.
Commenting on the PEA, Richard Lock stated:
“This is a significant start to the process of evaluating Santo
Tomas. The PEA firmly demonstrates the economic viability of the
Santo Tomas Project and justifies its continued development. The
combination of excellent infrastructure, simple metallurgy, a
cohesive and consistent grade distribution, and a low strip ratio,
along with the identification of several existing opportunities for
resource expansion, provide additional strength and certainty to
the Project. We have also identified a high probability of
additional upside in Project economics through the future
application of mine and process design improvements, all of which
confirm that we have a substantial resource at Santo Tomas. In
summary, the Santo Tomas Project clearly has robust potential for
the development of a large, low-cost open-pit, copper mining
operation.”
Santo Tomas Project PEA
OverviewThe Santo Tomas property comprises 9,034
ha of mineral concessions encompassing significant porphyry copper
mineralization in northern Sinaloa and southwest Chihuahua, Mexico.
The Project is located in the Santo Tomas Porphyry District, which
extends from Santo Tomas northward to the Jinchuan Group’s
Bahuerachi Project located approximately 14 km to the
north-northeast. The PEA was conducted using data (including 27,382
Cu assays) from 68 diamond drill holes (43,063 m) drilled by the
Company and 90 legacy reverse circulation and diamond drill holes
(21,075 m, for a total of 64,138 m in 158 drill holes) in the
Project’s North Zone and South Zone. The data from the seven
exploration diamond drill holes in Brasiles Zone and the single
geotechnical hole (GT001) drilled by the Company were excluded from
consideration in the MRE and PEA. Oroco’s entire updated drill hole
database (including PEA excluded holes) contains 166 new and legacy
drill holes totaling 69,556 m with lithological logging data and
29,992 Cu assays.
The commodity price assumptions for the
Discounted Cash Flow (“DCF”) analysis are
presented in Table 1. Key results are presented in Tables 2 &
3.
Table
1: PEA
DCF Price Assumptions
Commodity |
Unit |
Price* |
Cu |
US $ / lb |
3.85 |
Mo |
US $ / lb |
13.50 |
Au |
US $ / t.oz |
1,700 |
Ag |
US $ / t.oz |
22.50 |
*Cash flow model assumptions only
Table
2: Mining and Production –
Key Results
Key Assumptions |
Unit |
LOM |
Exchange Rate |
MXN / US$ |
19.76 |
Fuel Price |
MXN / L |
20.41 (US$1.03) |
Production Profile |
Unit |
LOM |
Total Open Pit Tonnage |
Mt |
1,831 |
Total Open Pit Mineralized Material Mined |
Mt |
848 |
Open Pit Strip Ratio |
Waste : mill feed |
1.16 |
Daily Throughput (Year 1 // Year 2 on) |
kt/d |
60 // 120 |
LOM concentrate production) |
Years |
20.1 |
Copper in Mill Feed |
M lb |
5,920 |
Molybdenum in Mill Feed |
M lb |
141.7 |
Gold in Mill Feed |
koz Au |
747.3 |
Silver in Mill Feed |
koz Ag |
54,998 |
LOM mill feed (Indicated // Inferred) |
Mt |
388 // 460 |
Average Cu payable / year – LOM |
M lb |
236 |
Average Cu payable / year – First 5 Years (1) |
M lb |
281 |
Payable (2) Copper LOM (in concentrate) |
M lb |
4,749 |
Payable Molybdenum LOM (in concentrate) |
M lb |
82.6 |
Payable Silver LOM (min 30 g/t payable in Cu Concentrate) |
koz |
26,330 |
Payable Gold LOM (min 1 g/t payable in Cu Concentrate) |
koz |
331.9 |
Operating Costs
(US$/lb.) |
Unit |
LOM |
C1 Cash Costs Copper (By-Product Basis) (3) |
US$/lb |
1.66 |
C3 Cash Costs Copper (By-Product Basis) (4) |
US$/lb |
2.00 |
Capital Expenditures
(5) |
Unit |
LOM |
Initial Capital (6) |
US$M |
1,339.9 |
Sustaining and Development Capital (6) |
US$M |
1,134.5 |
Closure Costs (5 years, year 20 - 24) |
US$M |
209.2 |
Estimated Salvage Value |
US$M |
0 |
Notes: |
|
(1) |
|
First 5 Years at full production, starting year 2. |
|
(2) |
|
Payable metals consider mining
dilution, concentrator recoveries and Treatment Charges/Refining
Charges (TC/RC). |
|
(3) |
|
C1 Cash Costs consist of mining
costs, processing costs, mine-level G&A and transportation
costs net of by-product credits. |
|
(4) |
|
C3 Cash Costs includes C1 Cash
Costs plus sustaining and expansion capital, royalties, and closure
costs and excludes expansion capital. |
|
(5) |
|
All capital expenditures are
inclusive of contingency provisions to allow for uncertain cost
elements, which are predicted to occur but are not included in the
cost estimate. |
|
(6) |
|
Net of leasing capital deferment
and leasing costs. |
|
|
|
|
Table
3: Key Financial Results and
Costs
Economics |
Unit |
LOM |
NPV at 8% (pre-tax // post-tax) |
US$M |
2,328.9 // 1,237.6 |
IRR (pre-tax // post-tax) |
% |
23.0 // 17.3 |
Payback (pre-tax // post-tax) |
Years |
4.1 // 5.0 |
Revenue over LOM |
US$M |
20,553 |
Initial Capital |
Mining Pre-Stripping (Capitalized Opex) |
US$M |
183.5 |
Mining Capital Equipment (1) |
US$M |
328.9 |
Total Mining (1) |
US$M |
512.4 |
Processing |
US$M |
976.1 |
Total Initial Capital (1) |
US$M |
1,488.5 |
Total Initial Capital Net of Leasing
(2) |
US$M |
1,339.9 |
Sustaining Capital |
Mining Equipment (3) |
US$M |
203.5 |
Processing |
US$M |
72.9 |
Total Sustaining Capital
(3) |
US$M |
276.4 |
Total Sustaining Capital Net of Leasing
(2) |
US$M |
467.5 |
Expansion Capital – Processing (year 2) |
US$M |
667.0 |
Operating Costs |
Mining Cost per tonne mined (4) |
US$ / t |
2.30 |
Mining Cost per tonne milled (4) |
US$ / t |
4.77 |
Processing Cost per tonne milled |
US$ / t |
4.25 |
G&A Cost per tonne milled |
US$ / t |
0.67 |
Total Operating Cost (3) |
US$ / t |
9.68 |
Notes: |
|
(1) |
|
Includes the full mining capital cost without deferral of capital
attributable to leasing in the amount of M$191.1 from initial
capital to sustaining capital. Excludes leasing costs in the amount
of M$42.4 incurred prior to production. |
|
(2) |
|
Supplier-sourced leasing terms
from October 2023 are used in the DCF model mine fleet cost
calculations that include a 5-year lease period with 10.3%
interest, 0.5% upfront fee, and no residual payment. |
|
(3) |
|
Includes sustaining capital
mining equipment without inclusion of costs attributable to the
deferral of initial mining equipment in the amount of M$191.1. |
|
(4) |
|
Excludes leasing costs. |
PEA Economic
SensitivitiesProject economics and cash flows are most
sensitive to changes in the price of copper (Figure 1). Mined grade
and recovery sensitivity is high and future studies will seek to
optimize these parameters. However, the highest potential for
change in economics is anticipated to result from future changes in
copper pricing.
Figure
1: Post-Tax NPV and
IRR Sensitivity Plots
PEA Mineral ResourcesThe PEA
MRE prepared by SRK Consulting (U.S.), Inc. in accordance with the
Canadian Institute of Mining, Metallurgy, and Petroleum
(“CIM”) Definition Standards (the “CIM
Standards”) incorporated by reference in National
Instrument 43-101 (“NI 43-101”), with an effective
date of October 11, 2023. The technical report will be prepared and
released by the Company and will be available at
www.orocoresourcecorp.com and on SEDAR (www.sedarplus.ca) under the
Company’s profile, within 45 days of this news release.
The mineral resource estimation process includes
updated structural, lithologic, and mineralization models, though
the PEA MRE has not materially changed from the previous study,
effective April 27, 2023, due to the inclusion of two additional
drill holes in the North Zone and updated economic assumptions
based on the PEA study. The Company provided SRK with an updated
exploration database including drill hole collar and downhole
survey data, geological logging, assay, specific gravity,
geotechnical classification, and associated information.
The resource estimation methodology involved the
following procedures:
- Database compilation and verification,
- Construction of wireframe models for the major structures,
lithotypes, and controls on mineralization,
- Definition of resource domains using a combination of
lithotypes, structure, and mineralization grade shells,
- Data conditioning (compositing and capping) for statistical and
geostatistical analyses,
- Determination of spatial continuity through variography within
the estimation domains,
- Block modeling and grade interpolation for all key economic
variables (Cu, Mo, Ag, Au, and Sulfur [S]) and secondary variables
(arsenic [As], calcium [Ca], potassium [K], lead [Pb], and zinc
[Zn]),
- Block model validation,
- Resource classification,
- Assessment of “reasonable prospects for eventual economic
extraction” (“RPEEE”) using a constraining
economic pit shell and selection of an effective cut-off grade
(“CoG”), and
- Preparation of the updated mineral resource statement.
SRK undertook the geological modeling and
mineral resource estimate using Seequent Leapfrog Geo and Leapfrog
Edge, respectively. The procedure involved construction of
wireframe models for structural geology controls, key geological
and mineralization domains, data conditioning (compositing and
capping) for statistical analysis, variography, block modeling and
grade interpolation followed by block model validation. Grade was
estimated using a combination of ordinary kriging and inverse
distance weighting cubed estimates for copper, molybdenum, gold,
and silver. Sulfur grades are estimated using inverse distance
weighting squared (“IDW2”) and bulk density is
estimated using a combination of simple kriging and IDW2. Grade
estimation was based on block dimensions of 50 m x 50 m x 10 m for
the PEA model (unchanged from the previous 2023 study). The block
size reflects current data spacing across the Project while
considering a likely open pit mining method. Classification of
mineral resources considers the geological complexity (structure,
lithology, alteration, and mineralization), spatial continuity of
mineralization, data quality, and spatial distribution of drilling
conducted at the Project.
The PEA MRE is supported by 64,138 m of drilling
in 158 holes. The drilling data represents a combination of holes
completed by Oroco from 2021 to 2023 and historical drill holes but
excludes drilling at Brasiles Zone and one geotechnical hole.
The PEA MRE includes the two primary
mineralization zones identified at Santo Tomas: North Zone and
South Zone. These zones display similar mineralization styles but
are physically separated by localized post-mineralization faults
and material currently defined as waste due to a lack of drilling.
Consistent with the previous study, the MRE is not constrained by
the location of the Huites Reservoir. Mineral resources are
reported above an effective cut-off grade (CoG) of 0.15% Cu and
constrained by an economic pit shell (see Table 4).
Table
4: Mineral Resource
Statement for the Santo Tomas Project, effective October 11,
2023
Category |
Zone |
TonnesMt |
Average Grade |
In-situ Metal |
CuEq% |
Cu% |
Mo% |
Aug/t |
Agg/t |
CuEq M lb |
Cu M lb |
Mo M lb |
Au koz |
Ag koz |
Indicated |
North Zone |
561.0 |
0.37 |
0.33 |
0.008 |
0.027 |
2.1 |
4,579 |
4,077 |
98.4 |
487.4 |
37,762 |
Total Indicated |
561.0 |
0.37 |
0.33 |
0.008 |
0.027 |
2.1 |
4,579 |
4,077 |
98.4 |
487.4 |
37,762 |
Inferred |
North Zone |
118.3 |
0.33 |
0.30 |
0.006 |
0.018 |
1.7 |
848 |
771 |
14.9 |
66.8 |
6,556 |
South Zone |
430.8 |
0.35 |
0.31 |
0.008 |
0.022 |
2.0 |
3,317 |
2,958 |
73.9 |
309.0 |
27,902 |
Total Inferred |
549.1 |
0.34 |
0.31 |
0.007 |
0.021 |
2.0 |
4,166 |
3,729 |
88.8 |
375.8 |
34,458 |
Notes: |
|
(1) |
|
Mineral resources are not mineral reserves and do not have
demonstrated economic viability. |
|
(2) |
|
Table abbreviations include: % =
percent, g/t = grams per metric tonne, Mlb = million pounds, Koz =
thousand troy ounces. |
|
(3) |
|
The mineral resources are
reported at an effective cut-off grade (CoG) of 0.15% Cu. |
|
(4) |
|
All figures are rounded to reflect
the relative accuracy of the estimates. Totals in the above table
may not sum or recalculate from related values in the table due to
rounding of values in the table, reflecting fewer significant
digits than were carried in the original calculations. |
|
(5) |
|
The mineral resources exclude
identified oxide mineralization due to a lack of confidence in
recovery assumptions of oxidized tonnages at this phase of the
Project. |
|
(6) |
|
Metal assays are capped where
appropriate. At the PEA level of the Project, it is the Company’s
opinion that all the elements included in the copper equivalent
calculation have a reasonable potential to be recovered and
sold. |
|
(7) |
|
All dollar amounts are presented
in U.S. dollars. |
|
(8) |
|
Bulk density is estimated on a
block basis using specific gravity data collected on diamond drill
core. |
|
(9) |
|
Reasonable prospects of eventual
economic extraction (RPEEE) are demonstrated through use of an
economic pit shell based on long-term copper price of $4.00/lb,
molybdenum price of $13.50/lb, a gold price of $1,700/oz, and a
silver price of $22.50/oz. Metal recovery factors used in the
determination of CoG and economic pit shell for Cu, Mo, Au, and Ag
have been applied based on metallurgical recovery calculations
based on average feed grade. A 45-degree slope angle was
applied. |
|
(10) |
|
The Huites Reservoir boundary was
ignored for the purposes of mineral resource determination. This is
consistent with the previous study. |
|
(11) |
|
The economic CoG was calculated
to be 0.11% Cu but for consistency with the previous study, Oroco
has elected to use an effective CoG at 0.15% Cu. CoG assumptions
include a copper price of $4.00/lb., mining cost of $2.27/t,
processing costs of $4.23/t, G&A costs at $0.65/t, mine
recovery at 98%, mean Cu recovery at 83.7%, and royalties at 1.5%,
have been applied in consideration of the RPEEE. |
|
(12) |
|
Equivalent Copper (CuEq) percent
is calculated with the formula CuEq% = ((Cu grade * Cu recovery
[83.7%] * Cu price) + (Mo grade * Mo recovery [59.1%] * Mo price) +
(Au grade * Au recovery [58.6%] * Au price) + (Ag grade * Ag
recovery [54.2%] * Ag price)) / (Cu price * Cu recovery [83.7%]).
It assumed that the Santo Tomas Project would produce a
conventional (flotation) copper concentrate product based on metal
recoveries indicated by PEA metallurgical test work and mean
Indicated Resource feed grades. |
|
(13) |
|
Reported contained individual
metals in the table above represent in-situ metal, calculated on a
100% recovery basis, except for CuEq% which applies mean recovery
assumptions (see Note 12). |
Mineralization has been identified
outside the current economic pit shell. The PEA highlights
the potential to define additional mineral resources on the
property. There is identified exploration potential for additional
mineralization in the southeastern and southwestern portions of the
South Zone based on observations from drilling and surface outcrops
in the area.
PEA Mine Design The PEA Mine
Design, prepared by Mining Plus, contemplates open pit development
that ensures no incursion upon the Huites Reservoir, maintaining a
100 m berm between the reservoir high water mark and the pit limit
thereby remaining outside of CONAGUA’s (Mexican water authority)
jurisdiction boundary (the “CONAGUA limit”). These
constraints were selected by the Company. Avoiding the CONAGUA
limit and applying a series of pit slope constraints derived from
preliminary geotechnical domains defined by SRK from Phase 1
drilling on the Project, a Mineral Resource within the ultimate pit
design (by classification and grades) for this PEA has been defined
as shown in Table 5.
Table
5: Pit Constrained Resource:
Mining-Plus
|
Indicated |
Inferred |
In-pit Resource(1) Mt |
387.98 |
459.70 |
Copper % |
0.340 |
0.297 |
Molybdenum % |
0.008 |
0.008 |
Gold g/t |
0.033 |
0.023 |
Silver g/t |
2.101 |
1.948 |
Notes: |
|
(1) |
|
The Mill Feed Tonnes and Grade are Mineral Resources, not Mineral
Reserves, but form part of the potential economic viability
analysis. |
|
(2) |
|
All dollar amounts are presented
in U.S. dollars (Note 3, below). |
|
(3) |
|
The marginal CoG was calculated
to be 0.14% CuEq (Cut off NSR = 7 $/t). CoG parameters include a
copper price of $3.80/lb., molybdenum price of $12.00/lb., gold
price of $1650/oz., silver price of $22.0/oz., processing costs of
$6.00/t, G&A costs at $1.00/t, mine recovery at 98%, developed
metallurgical recovery formulas, and royalties at 1.5%. CuEq is
calculated the formula CuEq% = [Cu grade * Cu recovery * (Cu price
– Selling cost Cu) + Mo grade * Mo recovery *(Mo Price - selling
cost Mo) + Au grade * Au recovery * (Au Price - selling cost Au) +
Ag grade * Ag recovery* (Ag Price - selling cost Ag)] / [(Cu Price
- selling cost) * Cu recovery]. |
|
(4) |
|
Metallurgical recovery formulas
were obtained from Ausenco’s “Oroco Resource Corp. Santo Tomas
Project Metallurgical Testwork Review June 9, 2023” report. |
The Mine Design proposes a standard open-pit,
truck and shovel operation with 10-meter bench intervals. Haul
trucks with a capacity of 194 tonnes will be used for hauling
mineralized material to the mineral processing plant, stockpile
facilities and the waste rock storage facility
(“WRSF”). Mining operations will use large-scale
mining equipment including 20 cm diameter blast hole drills, 29 m3
hydraulic shovel, 22 m3 front end loader, and 194 tonne capacity
haul trucks. Supplier-sourced capital costs from October 2023 are
used in the mine fleet cost calculations.
The mine is divided into two zones, the
higher-grade North Zone, which is the initial focus of mine
development, and the lower-grade South Zone, which requires
pre-stripping ahead of mine development. The North Zone pit is
approximately 1,850 m long (N-S) and 1,000 m wide (E-W) with a
depth of 680 m and the South Zone pit is 2,050 m long and 1,080 m
wide with a depth of 780 m.
The mining sequence consists of four phases. The
first and second phases define the North Pit, and the successive
two phases define the South Pit.
The Project has an operational LOM of 22.1
years, which includes two years of pre-stripping. The pit
constrained resource contains 388 million tonnes of indicated and
460 million tonnes of inferred resource and 983.6 million tonnes of
waste is removed, resulting in a strip ratio of 1.16 over the life
of the mine.
Mining operations will be carried out on a
24-hour per day, 365 days per year schedule. Milling will start at
60 kt/d in the first year of production, expanding to 120 kt/d in
the second year.
Mill feed tonnages and corresponding resource
classification are shown in Figures 2 and 3.
Figure
2: Preliminary Economic Assessment Mine
Plan and Schedule
Figure
3: Classification of
Material for Processing
Process Design & Plant
InfrastructureThe Q2 2022 metallurgical test work program
demonstrated the ability to produce a marketable copper concentrate
using a conventional flotation process flowsheet. Levels of
molybdenum in bulk concentrates were sufficient to produce a
marketable molybdenum concentrate using conventional Cu-Mo
separation flotation techniques. For purposes of the PEA,
logarithmic regression analysis was performed on the flotation test
work results to develop metallurgical process recoveries as a
function of head grade. Based on these formulas, Ausenco forecasts
the following mean recoveries for copper, molybdenum, silver, and
gold at 83.3%, 59.2%, 53.9%, and 53.2%, respectively. Results from
comminution test work on nine variability samples returned elevated
hardness properties for some of the mineralized materials (e.g. Axb
& ball mill work index of 30 and 18.3 kWh/tonne, respectively).
Given these measurements and high throughputs, High Pressure
Grinding Rolls (“HPGR”) crushing was considered
over conventional SAG milling. Figure 4 illustrates the simplified
overall process flowsheet developed for the Project.
Figure 4: Simplified
Process Flowsheet
The primary crusher is located at the north-east
end of the South Pit (see Figure 5). Coarse crushed material is
transported to a stockpile facility to the west of the process
plant via an overland conveyor. An alternative to this design would
involve the construction of conveyance tunnels and in-pit crushers
in both the North and South pits feeding the stockpile. Material
from the primary crusher is further reduced in size via secondary
crushing and HPGR before feeding into twin ball mills. Ground
material at a sizing of 80% passing 150 µm then advances to the
flotation circuit to produce a bulk rougher product that is
subsequently reground to 23 µm P80 prior to cleaner circuit
upgrading. The bulk cleaner concentrate advances to
copper-molybdenum separation to recover a molybdenum concentrate.
Gold and silver report to the copper concentrate. The tailings are
thickened and pumped to the tailings storage facility
(“TSF”). Copper and molybdenum concentrates are
dewatered prior to shipment.
Concentrates are trucked using the sealed
containerized method to the Port of Topolobampo situated on the
Gulf of California for transport to overseas smelters. The
containerized method removes the capital expense of a concentrate
storage facility at the port and loss of concentrate to the
environment. The proximity of rail infrastructure to the Project
could offer an alternative mode of concentrate transport.
Some infrastructure design includes expansion
capacity design features (e.g. overland conveyor, powerline and
water supply) during the initial phase so as to not interfere with
production during the expansion phase.
Figure 5: Mine
Infrastructure, Pits, Process Plant Layout, Tailings and Waste Rock
Storage Facilities
Tailings and Waste Rock Storage
FacilitiesBoth the waste-rock storage facility
(“WRSF”) and the TSF are designed in accordance
with national and international standards and constructed in
valleys west and east of the resource, respectively (see Figure 5).
The TSF has a rock fill with upstream composite liner system for a
starter embankment that transitions to a cycloned sand centerline
dam for the LOM with a seepage collection system in the downstream
foundation. Ditches and berms have been designed to capture
non-contact water above the facility and divert it around to reduce
water management in the TSF. The WRSF will be constructed from the
bottom up in thick lifts and contact water from the facility will
be captured with a water treatment facility at the toe of the
facility prior to release. Ditches and berms direct non-contact
water above the facility and divert it around.
Power Infrastructure and Water
SupplyElectrical supply is either from the Huites
hydroelectric plant down-stream from the Project or via built for
purpose combined cycle gas turbine plant tentatively located close
to the Huites power station and the Texas-Sinaloa natural gas
pipeline. Both options represent low carbon footprint power sources
for the estimated power requirements at similar costs. A 230-kVA
power line trace from Huites Station to the Project has been laid
out and costed, as has the main mine access route.
A make-up process water supply source is from
wells located within 25 km of the Project and follow a gravel
valley well source configuration similar to that employed during
mine operations at the El Sauzal Mine site located 45km upstream of
the Project and the historic Reforma Mine located 7 km to the
north.
Geology and
MineralizationPorphyry Cu (Mo‐Au‐Ag) mineralization on the
Santo Tomas property is closely associated with intrusives linked
to the Late Cretaceous to Paleocene (90 to 40 Ma) Laramide orogeny.
Santo Tomas and most of the known porphyry copper deposits in
Mexico lie along a 1,500 km‐long, NNW trending belt sub-parallel to
the west coast, extending from the southwestern United States
through to the state of Guerrero in Mexico.
In the Santo Tomas area, Mesozoic‐aged country
rocks comprising limestone, minor sandstones, conglomerates,
shales, and a thick succession of andesitic volcanics were intruded
by a range of Laramide age intrusions related to the Late
Cretaceous Sinaloa‐Sonora Batholith. Multiple phases are recognized
ranging from dioritic to monzonitic in composition.
Mineralization is strongly structurally
controlled by the Santo Tomas fault and fracture zone by the
pathway to quartz monzonite dikes, associated hydrothermal
alteration, hydrothermal breccias, and sulfide mineralization.
Sulfide minerals are dominated by chalcopyrite, pyrite and
molybdenite with minor bornite, covellite, and chalcocite. Sulfides
occur as fracture fillings, veinlets, and fine disseminations
together with potassium feldspar, quartz, calcite, chlorite, and
locally, tourmaline. Chalcopyrite is the main copper mineral with
minor copper oxides near surface.
Community and EnvironmentOroco
maintains an environmental and social plan for the Project
which provides a framework for its community outreach efforts
focused on education, ongoing employment, indigenous engagement and
community mapping. Oroco strives to maintain the support of the
community, local municipal leaders and state regulators and
governments in Sinaloa and Chihuahua. Oroco maintains its
exploration permits and approvals in good standing.
Additional baseline studies and initiatives in
key subject areas related to environmental, socio-economic,
cultural, and community engagement are planned. These studies and
activities will be necessary to advance the project and
provide a strong basis for the preparation of future
environmental studies and permitting.
Project Enhancement
OpportunitiesSeveral further opportunities to improve the
Project have been identified during the PEA Study. These include
but are not limited to:
- The application of sulfide leaching on lower grade chalcopyrite
resources currently assigned to waste. Preliminary studies have
commenced, and results are expected in Q4 2023. CAPEX/OPEX costs
for an SX/EW facility are developed but are not considered in this
PEA.
- Fully evaluate oxide copper resources that are currently
carried as waste in combination with sulfide leaching using
available data from surface sampling and drilling.
- Optimize mine plan around larger loading and haulage
equipment.
- Optimize mobile mining fleet considering mixed fuel and or
electrified options.
- Infill resource drilling in the area between North and South
zones: additional resource in that area would improve optimized pit
development and reduce mining costs.
- Additional comminution studies and variability testing to
better constrain recoveries across the full range of expected mill
feed grades based on rock and alteration types.
- Consider relocation of the primary crushing facility closer to
the pit(s) via in-pit crushing stations and conveyance via tunnels
from both North and South pits to the mill feed stockpile.
- Investigate coarse particle flotation to reduce comminution
costs and improve factors of safety on TSF design.
- Drill hydrogeological test wells at the north end of the North
Pit to better define pit inflow and pit dewatering costs.
- Drill selected geotechnical holes to optimize pit slope angles
and reduce mining of waste.
- Optimize heavy equipment leasing terms.
A geological-geochemical conceptual model will
inform the ongoing development and refinement of geochemical and
mine rock management plan for the site. The predicted occurrence of
large volumes of net neutralizing mine waste materials to be mined
in early years will be confirmed, as the buffering characteristics
of these waste materials can be effectively utilized as part of the
overall waste rock management strategy. Additional geochemical
assessment of the acid rock drainage / metal leaching risk for the
Project will be implemented to provide additional test work and
sampling coverage, and to confirm preliminary study findings.
Cautionary Notes to Investors
PEAThe reader is cautioned that the PEA is
preliminary in nature, and that it includes inferred mineral
resources that are considered too speculative geologically to have
the economic considerations applied to them that would enable them
to be categorized as mineral reserves, and there is no certainty
that the preliminary economic assessment will be realized.
Mineral Resource and Reserve
EstimatesIn accordance with applicable Canadian securities
laws, all Mineral Resource estimates of the Company disclosed or
referenced in this news release have been prepared in accordance
with the disclosure standards of NI 43-101 and have been classified
in accordance with the CIM Standards. Mineral Resources
that are not Mineral Reserves do not have demonstrated economic
viability. The estimate of mineral resources may be
materially affected by environmental, permitting, legal, title,
socio-political, marketing, or other relevant issues. In
particular, the quantity and grade of reported inferred mineral
resources are uncertain in nature and there has been insufficient
exploration to define these inferred mineral resources as an
indicated or measured mineral resource. It is uncertain in all
cases whether further exploration will result in upgrading the
inferred mineral resources to an indicated or measured mineral
resource category.
Qualified PersonsThe PEA for
the Project summarized in this news release was prepared by Ausenco
with input from SRK and Mining Plus, and will be incorporated in a
technical report prepared in accordance with NI 43-101 which will
be available under the Company’s SEDAR profile at www.sedarplus.ca
and on the Company’s website within 45 days of this news release.
The affiliation and areas of responsibility for each of the
Qualified Persons involved in preparing the PEA, upon which the
technical report will be based, are as follows:
Table
6: Qualified
Persons for
PEA
Qualified Persons |
Qualification |
Company (location) |
Position / Oversight |
James Norine |
P.E. |
Ausenco Engineering USA South Inc. (Tucson) |
Vice President, Southwest USA / PEA |
Shaida Miranda |
MSc, MAusIMM (CP), Mining Engineer |
Mining Plus SAC (Lima) |
Senior Mining Consultant / Mine Plan, Mining CAPEX + OPEX |
Ron Uken |
PhD, PrSciNat |
SRK Consulting (Canada), Inc. (Vancouver) |
Principal Structural Geologist / Geology |
Scott Burkett |
RM-SME |
SRK Consulting (U.S.), Inc.(Denver) |
Principal Consultant / Resource Geology |
Andy Thomas |
MEng, BE, P.Eng., EGBC |
SRK Consulting (Canada), Inc. (Vancouver) |
Principal Rock Mechanics Engineer / Geotechnical (Preliminary) |
Peter Mehrfert |
P. Eng. |
Ausenco Engineering Canada Inc. (Vancouver) |
Principal Process Engineer / Metallurgy |
James Millard |
M. Sc, P. Geo. |
Ausenco Sustainability Inc. (Victoria) |
Director, Strategic Projects / Environmental, Social,
Permitting |
Scott Elfen |
P.E. |
Ausenco Engineering Canada Inc. (Vancouver) |
Global Lead Geotechnical Services / TSF & WRSF design +
geotechnical |
Each QP has reviewed and verified the content of
this news release.
About OROCO The Company holds a
net 85.5% interest in those central concessions that comprise 1,173
hectares “the Core Concessions” of The Santo Tomas Project, located
in northwestern Mexico. The Company also holds an 80% interest in
an additional 7,861 hectares of mineral concessions surrounding and
adjacent to the Core Concessions (for a total Project area of 9,034
hectares, or 22,324 acres). The Project is situated within the
Santo Tomas District, which extends up to the Jinchuan Group’s
Bahuerachi Project, approximately 14 km to the northeast. The
Project hosts significant copper porphyry mineralization defined by
prior exploration spanning the period from 1968 to 1994. During
that time, the Project area was tested by over 100 diamond and
reverse circulation drill holes, totalling approximately 30,000
meters. Commencing in 2021, Oroco conducted a drill program (Phase
1) at Santo Tomas, with a resulting total of 48,481 meters drilled
in 76 diamond drill holes. In May of 2023, the Company completed a
Mineral Resource Estimate for the Core Concessions that identified
Indicated and Inferred resources of 487 Mt @ 0.36% CuEq and 600 Mt
@ 0.36% CuEq respectively. This news release updates that resource
identifying Indicated and Inferred resources of 561 Mt @ 0.37% CuEq
and 549 Mt @ 0.34% CuEq respectively.
The Project is located within 160 km of the
Pacific deep-water port at Topolobampo and is serviced via highway
and proximal rail (and parallel corridors of trunk grid power lines
and natural gas) through the city of Los Mochis to the northern
city of Choix. The property is reached, in part, by a 32 km access
road originally built to service Goldcorp’s El Sauzal Mine in
Chihuahua State.
Additional information about Oroco can be found
on its website at www.orocoresourcecorp.com and by reviewing its
profile on SEDAR at www.sedarplus.ca.
For further information, please contact:
Richard Lock, CEOOroco Resource Corp. Tel:
604-688-6200 Email: info@orocoresourcecorp.com
www.orocoresourcecorp.com
Cautionary Note Regarding
Forward-Looking Information
This news release contains “forward-looking
information” within the meaning of applicable Canadian securities
legislation based on expectations, estimates and projections as at
the date of this news release. Forward-looking information involves
risks, uncertainties and other factors that could cause actual
events, results, performance, prospects and opportunities to differ
materially from those expressed or implied by such forward-looking
information. All statements other than statements of fact included
in this document constitute forward-looking information, including,
but not limited to, objectives, goals or future plans, statements
regarding anticipated exploration results and exploration plans,
Oroco’s expectations regarding the future potential of the Santo
Tomas deposits, its plans for additional drilling and other
exploration work on the Santo Tomas deposits and the potential to
advance or improve the PEA study.
Forward-looking information is not, and cannot
be, a guarantee of future results or events. Forward-looking
information is based on, among other things, opinions, assumptions,
estimates and analyses that, while considered reasonable by the
Corporation at the date the forward-looking information is
provided, inherently are subject to significant risks,
uncertainties, contingencies and other factors that may cause
actual results and events to be materially different from those
expressed or implied by the forward-looking information.
Factors that could cause actual results to
differ materially from such forward-looking information include,
but are not limited to, capital and operating costs varying
significantly from estimates; the preliminary nature of
metallurgical test results; delays in obtaining or failures to
obtain and comply with required governmental, environmental or
other Project approvals; uncertainties relating to the availability
and costs of financing needed in the future; changes in equity
markets; inflation; fluctuations in commodity prices; delays in the
development of the Project; COVID-19 and other pandemic risks;
those other risks involved in the mineral exploration and
development industry; and those risks set out in the Company’s
public documents filed on SEDAR at www.sedarplus.ca.
Should one or more risk, uncertainty,
contingency or other factor materialize or should any factor or
assumption prove incorrect, actual results could vary materially
from those expressed or implied in the forward-looking information.
Accordingly, you should not place undue reliance on forward-looking
information. Oroco does not assume any obligation to update or
revise any forward-looking information after the date of this news
release or to explain any material difference between subsequent
actual events and any forward-looking information, except as
required by applicable law.
Neither the TSX Venture Exchange nor its
Regulation Services Provider (as that term is defined in the
policies of the TSX Venture Exchange) accepts responsibility for
the adequacy or accuracy of this news release. No stock exchange,
securities commission or other regulatory authority has approved or
disapproved the information contained herein.
All figures in this announcement are available at : Oroco
Resource October 17, 2023 PEA Figures
Oroco Resource (TSXV:OCO)
Historical Stock Chart
From Nov 2024 to Dec 2024
Oroco Resource (TSXV:OCO)
Historical Stock Chart
From Dec 2023 to Dec 2024