Oroco Announces $2.3 Billion Pre-tax NPV in a PEA for the Santo Tomas Project Pre-Tax NPV (8%) of US$2.3 Billion, After-Tax NPV (8%) of US$1.2 Billion Pre-Tax IRR of 23.0% After-Tax IRR of 17.3% Average annual copper production of 292 M lb per year over first 5 years of full production

October 17th, 2023 News Release

Oroco Announces $2.3 Billion Pre-tax NPV in a PEA for the Santo Tomas Project

Pre-Tax NPV (8%) of US$2.3 Billion, After-Tax NPV (8%) of US$1.2 Billion

Pre-Tax IRR of 23.0% After-Tax IRR of 17.3%

Average annual copper production of 292 M lb per year over first 5 years of full production

VANCOUVER, CANADA, October 17 th, 2023 – 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 Overview

The 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 Sensitivities

Project 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 Resources

The 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 Tonnes

Mt

Average Grade In-situ Metal

CuEq

%

Cu

%

Mo

%

Au

g/t

Ag

g/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 m 3 hydraulic shovel, 22 m 3 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 Infrastructure

The 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.

-

0.05

0.10

0.15

0.20

0.25

0.30

0.35

0.40

0.45

0.50

-

20,000

40,000

60,000

80,000

100,000

120,000

Metal Grade (%)

Total Material Movement (kt)

Mine to Mill Stockpile to Mill Mine to Stockpile Mine to Waste Dump

Processing capacity CuEq % Cu%

-

10,000

20,000

30,000

40,000

50,000Material Movement (kt)

Total Material Mined for Mill Feed by Classification

Indicated Inferred

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.