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RIO2 Limited Completes Updated Pre-Feasibility Study FOR the Fenix GOLD Project IN Chile

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RIO2 LIMITED COMPLETES UPDATED PRE-FEASIBILITY STUDY

FOR THE FENIX GOLD PROJECT IN CHILE

For Immediate Release September 4, 2019

Rio2 Limited (“ Rio2” or the “Company ”) (TSXV: RIO; OTCQX: RIOFF; BVL: RIO) today announces the

results of the updated mineral resource estimate (“ MRE”) and P re-Feasibility Study (“PFS”) for its

100% owned Fenix Gold Project (“Fenix Gold” or the “Project”) located in the Maricunga Mineral Belt

of the Atacama Region, Chile. This updated PFS is the Company’s base case to accelerate development

and start production in the shortest possible time.

All amounts in this news release are in US dollars unless otherwise indicated. Base case economics for

this PFS were calculated using a $1,300 per oz gold price.

The updated MRE for the Project is 5.0 million oz of gold in the measured and indicated category and

1.4 million oz of gold in the inferred category constrained within a $1,500 gold price pit shell. The

mineral resource remains open at depth and along strike.

This PFS is strategically focused on an optimally configured mine plan which will facilitate the shortest

possible timeline to construction/production, a lower initial capex, higher grades initially being mined,

and a lower initial strip ratio as compared with the 2014 PFS. The PFS focuses on a low-cost heap leach

gold mine with 1.83 million ounces (“oz”) of gold reserves that will produce 1.37 million oz of gold.

The PFS contemplates mining ore at a rate of 20,000 tonnes per day (“tpd”) with water for the project

being trucked from Copiapo. This compares with the ore mining rate of the 2014 PFS which was a

constant 80,000 tpd with water for the project being piped from Copiapo. To maximize cash-flow,

high-grade ore will be placed on the leach pad during the initial 13 years of production and low-grade

ore will be stockpiled for leaching in the subsequent 3 years of production giving a total mine life of

16 years. Average annual gold production during the first 13 years will be 93,000 oz and 50,000 oz

during the final 3 years of production as stockpiled ore is being crushed and leached.

With a large mineralized resource and potential for resources to grow through further drilling, there

remains considerable opportunity to increase annual production and extend the mine life of the Fenix

Gold Project. Timing to increase production will depend on transporting a greater volume of water via

a pipeline, alternative water solutions closer to the project and changes to the gold price during the

initial years of production.

The previously completed Pre- Feasibility Study on the Project, titled “NI 43-101 Technical Report on the Cerro Maricunga Project Pre-

Feasibility Study Atacama Region, Chile” dated October 6, 2014 with an effective date of August 19, 2014 (the “2014 PFS”), is available on

SEDAR under Rio2’s SEDAR profile at www.sedar.com. The Cerro Maricunga Project was renamed the Fenix Gold Project by Rio2 in 2018.

PFS HIGHLIGHTS

• 1.83 million ounces (“oz”) of Proven & Probable Mineral Reserves grading 0.49 grams per tonne

("g/t") gold

High-grade to leach pad – 81.9 million tonnes grading 0.57 g/t gold

Low-grade to stockpile – 33.1 million tonnes grading 0.30 g/t gold

• $222 million after-tax life of mine ("LOM") cumulative cash flow (unlevered)

• $997 / oz average LOM all-in sustaining costs ("AISC")

• 1.37 million oz LOM gold production

• 93,000 oz average annual gold production during initial 13 years

• 50,000 oz average annual gold production during final 3 years

• $121 million after-tax net present value discounted at 5% (“NPV5”) or ($241 million at $1,500 per

oz gold)

• 27.4% internal rate of return ("IRR") (44.3% at $1,500 per oz gold)

• Capital costs of $111 million with LOM sustaining capital costs of $95 million

• Construction currently targeted for Q4 2021 and first gold production in Q4 2022

• 16 year mine life at initial 20,000 tpd mining rate with expansion potential subject to additional

water options and changes to the gold price

Alex Black, President & CEO of Rio2, stated, “Our highly skilled and experienced management team

has taken great stride s since the acquisition of the Fenix Gold Project just over 12 months ago. We

have completely re-imagined and re-engineered the project with a focus on shortening the timeline

to construction/production, simplifying the approval process and permitting of the project, lowering

initial capex, concentrating on higher grades during early years of production and optimally minimizing

the initial strip ratio. We also thought outside of the box to arrive at an innovative solution of trucking

water to the project with the sole purpose of fast-tracking and simplifying the approvals process and

permitting of the project. Together with our highly experienced environmental and permitting

consultants in Chile, Minería y Medio Ambiente Limitada (MyMA), we have now set an achievable

timetable to construction in Q4 2021. With a large mineralized resource base and a modest project

production rate, as indicated in this PFS, we are confident we can expand the mine quickly and

optimally after achieving initial production. Once the Fenix Gold Project achieves commercial

production it will be the only gold oxide heap leach gold mine in operation in Chile and achieving a

unique milestone.”

OVERVIEW

This PFS focuses on the development of the Fenix Gold Project on a throughput of 20,000 tpd. The

primary reason Rio2 has elected to start at this rate of production is to allow for the trucking of water

from Copiapo which will expedite and simplify the approval and permitting process of the mine. By

choosing the option of trucking water to the mine site, the Company has reduced the timeline to

construction from five years to two years. Once the project is in production, the Company will focus

on the logistics and timing of constructing the previously planned water pipel ine from Copiapo

(outlined in the 2014 PFS) which will sustain a mining rate of up to 80,000 tpd, four times of what is

contemplated in this PFS.

Under the PFS mine plan, the Project will be able to produce for sixteen years with average annual

production of 85,000 oz of gold for total LOM production of 1.37 million oz. LOM AISC is estimated at

$997/oz. The Project demonstrates strong returns with an after-tax NPV5 of $121 million and an after-

tax IRR of 27.4% using the base case gold price of $1,300/oz ($241 million and 44.3% at $1,500/oz gold

price). The Project is expected to generate average annual after-tax net operating cash flow of $15.1

million with cumulative LOM after -tax net cash flow of $222 million. At $1,500/oz gold, the Project

would average more than $25 million in after-tax net operating cash flow annually and generate more

than $422 in cumulative after-tax net cash flow over the 16-year mine life.

PFS HIGHLIGHTS

High-grade Low-grade Total 2014 PFS

Gold Price $1,300 / oz $1,300 / oz $1,300 / oz $1,350 / oz

Ore Tonnes 81.9M 33.1M 115M 294M

Grade (Au g/t) 0.57 0.30 0.49 0.40

Proven &Probable Reserve (Au ozs) 1,829,000 3,743,000

Average Annual Gold Production (Au ozs) 93,000 50,000 85,000 228,000

Recoverable Gold (Au ozs) 1,371,000 2,956,000

Throughput (tonnes per day) 20,000 20,000 20,000 80,000

Strip Ratio 0.81 1.76

Recovery (%) 75 75 75 79

Mine Life (years) 13 3 16 13

Initial Capex $111 $399

Sustaining Capex $95 $188

Cash Cost (US$ / oz) $918 $1,036 $927 $864

AISC (US$ / oz) $979 $1,082 $997 $928

Pre-tax NPV (0% - $M) $305

Pre-tax NPV (5% - $M) $168 $521

Pre-tax IRR (%) 31.9 29

Post-tax NPV (0% - $M) $222

Post-tax NPV (5% - $M) $121 $409

Post-tax IRR (%) 27.4 25

ECONOMIC SENSITIVITIES

Using the base case gold price of $1,300/oz and incorporating only Proven and Probable Mineral

Reserves of 1,829,000 oz of gold, the Project has an after- tax NPV (5%) of $121 million and an after-

tax IRR of 27.4%. The Project’s economics are most sensitive to fluctuations in the gold price and

operating costs, as summarized in the tables below.

Sensitivity to Gold Price

Gold Price ($/oz) $1,200 $1,300 $1,400

NPV (5% after tax) $60M $121M $181M

IRR (after tax) 17.5% 27.4% 36.1%

Sensitivity to Capital Costs

Capital Costs -10% $111M 10%

NPV (5% after tax) $128M $121M $113M

IRR (after tax) 31.2% 27.4% 24.3%

Sensitivity to Operating Costs

Operating Costs -10% $1,272M 10%

NPV (5% after tax) $176M $121M $65M

IRR (after tax) 34.9% 27.4% 18.8%

CAPITAL & OPERATING COSTS

Initial Capital for the Project is estimated at $111.2 million which includes $14.2 mill ion in

contingencies. Capital cost estimates are summarized in the table below.

Area Capex ($Millions) Sustaining

($Millions) Total ($Millions)

Mining 3.25 0.85 4.10

Process Plant 34.64 16.27 50.91

Support Facilities 19.48 19.48

Indirect Cost of process Plant and support facilities 16.77 16.77

Process Plant Contingency 10.63 10.63

Leach Pad, Waste dump, PLS Ponds 11.55 44.09 55.64

Leach Pad, Waste dump, PLS Ponds Contingency 3.60 13.81 17.41

Owner costs 11.30 4.570 15.87

Closure Costs 0.00 15.40 15.40

Sub Total 111.22 94.99 206.21

Operating cost estimates are summarized in the table below.

Cost Area $/oz $/tonne

Mining ($ mined) 1.8

Reclaimed ore from

stockpile 0.91

Haulage Crusher to Pad 0.65

Mining ($ processed) 368.8 4.4

Processing ($ processed) 340.6 4.1

G&A ($ processed) 166.7 1.99

Total On-site Costs 876.1

Refining, transport 50.27

Total Cash Costs 926.4

Royalties 0.97

Total Cash Costs 927.3

Sustaining Capex 69.26

AISC 996.6

The mining cost considers the mining of ore, the mining of waste, reclaiming low -grade ore from the

stockpile to the crusher, and from the crusher to the pad.

The processing cost considers crushing and leaching, recovery, and the water supply costs.

MINERAL RESOURCES & RESERVES

The Mineral Resource for the Fenix Gold Project has been updated with the results from a small infill

reverse circulation (RC) drill program of 7,066 m completed in 2018/19, and all relevant and approved

surface channel sampling ha ve been used in the resou rce estimate for the first time. This resource

update also marks the first time that a three dimensional (3-D) geological model has been constructed

for the deposit.

The additional data, new geological model and revised modelling parameters have had no ma terial

effect on the combined measured and indicated resources when compared to the 2014 PFS. This

suggests that the resource estimate is robust for bulk mining.

Inferred resources have increased markedly from the 2014 PFS due to confidence gained from th e

geological model and well-structured variograms. Inferred resources have been projected up to 150

m from the base of drilling, in line with ranges demonstrated in gold variograms.

The MRE presented in the following table are constrained within a $1,500/oz optimized open pit and

calculated using a 0.15 g/t cut-off grade.

Resource Classification Million Metric Tons Au Grade (g/t) Au Ounces (x1000)

Measured 122.4 0.41 1,630

Indicated 288.3 0.36 3,355

Total Measured + Indicated 410.7 0.38 4,985

Inferred 136.6 0.32 1,388

Notes:

1. Mineral Resources reported is inclusive of mineral reserves;

2. The table includes all Measured, Indicated, and Inferred Resources contained within the “Resource Pit”, which represents t he test for

eventual extraction applied;

3. Mineral Resources are not Mineral Reserves and do not have demonstrated economic viability. There is no certainty that all or any part

of the Mineral Resources estimated will be converted into Mineral Reserves;

4. Mineral Resources are reported in accordance with Canadian Securities Administrators (CSA) National Instrument 43 -101 (“Standards of

Disclosure for Mineral Projects” (NI 43-101) and have been estimated in conformity with generally accepted Canadian Institute of Mining,

Metallurgy and Petroleum (CIM) "Estimation of Mineral Resource and Mineral Reserves Best Practices" gu idelines;

5. Mineral resource tonnage and contained metal have been rounded to reflect the accuracy of the estimate, and numbers may not add due

to rounding;

6. The quantity and grade of reported Inferred resources in this estimation are uncertain in nature and there has been insufficient

exploration to define these Inferred resources as an Indicated or Measured mineral resource and it is uncertain if further ex ploration will

result in upgrading them to an Indicated or Measured mineral resource category.

The Mineral Reserves presented in the following table are constrained within a $1, 225/oz optimized

open pit and are reported as in-situ dry million tonnes and include 3% mining dilution and 97% mining

recovery using a cut-off grade of 0.24 g/t Au.

Reserve Category Million

Tonnes

Grade

(Au g/t)

Contained Gold

(Koz)

Recoverable Gold

(Koz)

Proven 53 0.52 866 650

Probable 63 0.47 962 722

Proven and Probable 116 0.49 1,828 1,372

Notes: The Mineral Reserve estimate with an effective date of August, 15 2019 is based on the Minera l Resource estimate with the same

effective date that was prepared by Mario Rossi, Principal Geostatistician of GeoSystems International Inc. The Mineral Reserve was

estimated by Mining Plus with supervision by Raul Espinoza, Senior Open Cut Engineer with Mining Plus Peru S.A.C. Mineral Reserves are

estimated within the final designed pit which is based on the $1,225 /oz pit shell. The minimum cut-off grade was 0.24 g/t gold. Average life

of mine costs are $2.42/tonne mining, $4.10/tonne processing, and $1.99/tonne processed G&A. The average process recovery was 75%

for single stage crushing. Tonnes and gold ounces are both re ported in millions. Small differences in total tonnage and grade may occur due

to rounding. The Mineral Resource estimate is inclusive of Mineral Reserves.

FENIX GOLD PROJECT - MINE PLAN

During Year 1 the mine production rate will be ramped up to 20,000 tpd of high-grade ore (> 0.40 g/t)

for estimated gold production of 80,000 oz. The life of mine strip ratio (waste : ore) is estimated to be

0.81 : 1.

Mining will then progress for an additional 12 years at an average annualized rate of 20,000 tpd of

high-grade ore, 7,000 tpd of low-grade ore and associated waste material. The high-grade ore will be

crushed via a single stage crusher to a P 80 size of 4 inches then re-handled and sent to the leach pad

whilst the low-grade ore is stockpiled for crushing and leaching in later years.

Metallurgical test work shows average life of mine recoveries of 75% after single stage crushing to 4

inches, with more than 50% of the gold recovered during the first 45 days of leaching.

Mine design and estimation of the mining reserves was completed using conventional open-pit design

methodology. The mine design is based on a $1,225 Lerchs -Grossmann pit optimisat ion computer

analysis. The pit design incorporates 20m benches made up of 2 x 10m mining benches utilizing a fleet

of 70 tonne and 90 tonne excavators and 43 tonne dump trucks. Mining operations will be performed

exclusively by a mining contractor under a mining alliance style framework for the entire life of mine.

Fenix Gold Project – Mine Site Layout

For a picture of the Fenix Gold Project Mine Site Layout click here.

PROCESSING

High-grade ore will be crushed to a P 80 size of 4 inches via a single stage Gyratory crusher wit h lime

dosing occurring before the crushed ore is fed to a stockpile. Crushed ore will be re -handled and

trucked from the crushed ore stockpile to the leach pad. Agglomeration of crushed ore is not required.

Low-grade ore will be mined and stockpiled for crushing and leaching in later years.

Processing operations will treat the solutions from the heap leach facility operating in a new ADR

(adsorption, desorption and refining) plant capable of treating 20,000 tpd of ore to pad or 1,058 cubic

meters per hou r of pregnant solution to produce doré bars. The plant layout is designed to be

upgradeable to 40,000 tpd and 80,000 tpd respectively.

Processing costs are estimated at $4.10 per tonne treated over the current life of mine which includes

water purchase and water transport costs.

HEAP LEACH PAD

The leach pad area will be prepared and covered with an impermeable liner. Corrugated, perforated

drainage piping will be laid on the liner for collection of the pregnant leach solution. A protective layer

of finely crushed, permeable ore will be placed on top of the liner to prevent damage from the mobile

equipment and during ore loading. The ore will be stacked on the pad in 10m lifts.

The heap leach pad is located 4 km from the pit, at an elevation of 4,376m abo ve sea level. The pad

will be developed in four stages with a stacking volume for Stage 1 of 10.3 Mt; 30. 6 Mt for Stage 2;

27.7 Mt for Stage 3 and 60.7 Mt for the final stage. The total pad capacity will be 129 Mt. The irrigation

system will uniformly apply cyanide solution directly onto the levelled surface of the leach pile through

a drip irrigation system, at an irrigation rate of 10 L/hm2 with an irrigation cycle of 90 days.

The percolation rate through the heap will depend on the viscosity and specific gravity of the solution,

the mineral void space, the percentage of fines, mineral affinity for the solution and air entrapment.

Once the heap is saturated, the gold rich solution will drain to the lowest part of the pad and then into

the pregnant leach solution (PLS) pond before being pumped to the ADR processing plant.

POWER

The power supply for the Project will be generated via diesel generators. T hree generators, two in

continuous operation and one on standby, will be installed in the power plant located in the ADR plant.

There will also be two generators installed at the crusher which will also supply power to the mine

workshops.

Grid power is located within 25 km of the mine site and connection to the grid will be considered as

the Fenix Gold Mine is expanded.

WATER

The 20,000 tpd project requires a water supply of up to 24 L/s. The Fenix Gold Project has access to

water via a contract signed with Aguas Chañar S.A. (“Aguas Chañar”), the major water supplier to the

town of Copiapo, to supply up to 80 L/s of treated town wastewater from its Piedra Colgada treatment

facility located to the north of C opiapo. The original plan , outlined in the 2014 PFS, was to build a

pipeline with associated power line from the Aguas Chañar facilities to Fenix Gold along the existing

main road, international road CH31, from Copiap o to Argentina which passes within 20 k m of the

Project. This plan is still being considered for the future expansion of the Project and discussions are

ongoing with infrastructure companies who are interested and able to finance and build the pipeline

and other mining companies who may wish to share in the benefit of the pipeline project. The capital

costs, operating costs and cost of water for the larger water solution are set out in the 2014 PFS.

The water for the 20,000 tpd project will be t ransported by 30 tonne capacity w ater tankers,

loading from the Aguas Chañar facility and discharging to the process plant located at the Project, a

distance of approximately 158 km. The water transport route will be via international road CH31 which

passes within 20 km of the mine site.

Water costs are estimated to be $1.56 per tonne of ore processed for the first four years of production

and decrease to $1.51 per tonne for the remaining life of the project. The water cost includes the

purchase price and transportation of the water to site.

The Company is currently reviewing a number of additional water options involving permitted, unused

water rights which are closer to the planned mining operations with the objective of improv ing the

economics of the water supply to the Project.

LABOR AND SUPPLIES

The Fenix Gold Project is located approx imately 140 km from Copiapo, a mining town with a

population of approximately 175,000 people that supports major mining o perations in the a rea.

Skilled labour, specialist services and materials for the mining operations will be sourced locally. An