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Erdene Provides Updates ON Exploration at the Dark Horse GOLD Prospect and Bayan Khundii GOLD Project

Exploration Programs

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ERDENE PROVIDES UPDATES ON EXPLORATION AT THE DARK

HORSE GOLD PROSPECT AND BAYAN KHUNDII GOLD PROJECT

Press Release

Halifax, Nova Scotia

2021.04.08

Erdene Resource Development Corporation (TSX:ERD | MSE:ERDN) (“Erdene” or the

“Company”) is pleased to provide an update on exploration at the new Dark Horse gold

prospect as well as announcing the launch of an Employment Orientation program and

advise on the current COVID-19 situation in Mongolia.

Highlights1(See the attached maps and images for reference):

• Drilled nine scout holes totalling 1,900 metres in February 2021 to define the extent

of the delineation program at the main Dark Horse Prospect

o Holes AAD-65 to AAD-67, in the northern half of the target, intersected broad

zones of alteration, establishing continuity and supporting further drilling:

§ AAD-65 returned 7 metres of 1.15 g/t gold beginning 113 metres

downhole

§ AAD-66 returned 14 metres of 1.31 g/t gold beginning 53 metres

downhole, as well as 20 metres of 1.74 g/t gold, beginning 112 metres

downhole

§ AAD-67 returned 6 metres of 0.32 g/t gold beginning 110 metres

downhole

o Holes AAD-68 to AAD-73, testing areas peripheral to the north-south structure

intersected gold and/or pathfinder elements:

§ AAD-68 returned 2 metres of 1.41 g/t gold beginning 192 metres

downhole

§ AAD-70 returned 2 metres of 4.24 g/t gold beginning 64 metres downhole

• Commenced 3,000 metre delineation drilling program in late March

o Delineation drilling will utilize 100-metre fence spacing along the main trend

o Approximately 600 metres will target the southern extension of the trend

(including the area around AAD-58, which intersected 45m of 6 g/t gold)

o Results are pending for ~1,100 metres of core, currently at the lab

• Completed geophysical modelling, surface sampling, spectral analysis and other

work over a 4 by 3 kilometre area in advance of further exploration

o Studies continue to improve Erdene’s understanding of the mineralization in

the greater Dark Horse area

• Launched an Employment Orientation program at the Bayan Khundii Project camp

for local community members

1 Reported intervals in this release are downhole apparent widths. Continued exploration is required to confirm anisotropy of

mineralization and true thicknesses.

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o Two cohorts of 36 received training from Erdene’s HSEC team

o Further 140 residents are registered for upcoming sessions

• Bayankhongor province registered its first COVID-19 infection on March 24

o Provincial government has introduced precautionary measures in response

o Erdene provided relief funding to the Provincial Emergency Commission

o Dark Horse drilling continues with appropriate COVID safeguards

Quotes from the Company:

“Following the announcement of the exciting Dark Horse gold discovery in January 2021,

our technical team completed a staged exploration plan over the past quarter,” said Peter

Akerley, Erdene’s President and CEO. “This Q1 program confirmed continuity of a gold

mineralized system along a 1.2 km north-south trending structure and improved our

understanding of the discovery and its setting relative to the Bayan Khundii Deposit and

the large Ulaan -Khundii alteration system , which we believe hosts a much more

significant gold mineralizing event and hydrothermal alteration system than previously

recognized.”

“In late March we commenced a 3,000 metre shallow delineation drilling program on the

main Dark Horse discovery area,” continued Mr. Akerley. “Although focused on the 1.2km

northern portion of the Dark Horse structure, testing will cover a 2.5km strike length. The

first batch of core is currently in the lab with results expected to be announced in the

coming weeks.”

“Although we have been able to continue fieldwork with minimal disruption, Mongolia has

seen increasing spread of COVID -19, including the first reported cases in our host

province of Bayankhongor,” concluded Mr. Akerley. “We are taking all precautions to

maintain a safe work environment. Furthermore, we recently provided funding to the local

provincial emergency commission to ensure the safety of local residents. We are closely

monitoring the COVID situation in the country and its impact on the start of construction

of our Bayan Khundii Gold Project.”

Q1 2021 Dark Horse Exploration Program Overview

Erdene carried out the following exploration at the Dark Horse prospect during Q1 2021:

• Completed a nine-hole, 1,900 metre drill program, carried out by Falcon Drilling,

Ulaanbaatar, Mongolia;

• Completed d etailed surface mapping and sampling, co nducted by Erdene’s

Mongolian technical team;

• Completed geophysical modelling and interpretation with the assistance of Wave

Geophysics, Denver Colorado;

• Completed s urface and downhole spectral alteration mineral analysis and

interpretation with Plus Minerals LLC, Ulaanbaatar;

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• Commenced m ineralogic and petrographic analysis and interpretation using

APSAR Geoscience, New Zealand;

• Commenced p reliminary metallurgical testing using ALS Laboratories,

Ulaanbaatar; and

• Continued c onsultation with Dr. Jeffrey Hedenquist, Ottawa, on the style and

characteristics of the mineralized system at Dark Horse and within the larger

Khundii alteration system.

These studies and a nalyses continue to improve Erdene’s understanding of the Dark

Horse Discovery and its geologic setting relative to the nearby Bayan Khundii epithermal

gold deposit, as well as the greater Ulaan-Khundii quartz-sericite-pyrite alteration footprint.

Exploration results show evidence of a widespread mineralizing hydrothermal system

consistent with many of the world ’s major epithermal gold deposits. Evidence suggests

that Dark Hors e shares a structural relationship with the Bayan Khundii gold deposit

through a 4-kilometres long N-S trending dilation zone connecting the two project areas.

Drill Results – Q1 2021

The Q1 -2021 drill program was designed to collect geologic information for the

surrounding area and define the area of interest for more detailed drilling. The majority

of targets were cross -cutting or parallel structures with limited testing of the norther n

portion of the Dark Horse target area.

In February 202 1, the company drilled nin e holes at the D ark Horse prospect, totalling

1,900 metres . Three holes, AAD-65 through AAD -67, were drilled along the north ern

portion of the 1.2 km Dark Horse target area . The remaining holes were drilled in areas

peripheral to the trend with one hole, AAD-71, testing the main structure 1km south of the

nearest drilling (AAD-58).

Table 1 below, includes highlights from the program.

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Table 1 - Dark Horse Scout Drilling Highlights

Hole From To Interval (1) g/t Au (2)

Along N-S

Structure

AAD-65 113 120 7 1.15

and 128 142 14 0.51

and 196 205 9 0.69

AAD-66 53 67 14 1.31

and 112 132 20 1.74

and 137 139 2 0.96

AAD-67 110 116 6 0.32

Peripheral

Areas AAD-68 192 194 2 1.41

and 250 252 2 0.47

AAD-70 52 53 1 0.66

and 64 66 2 4.24

and 110 116 6 0.33

1 Reported intervals are apparent thicknesses (i.e. downhole widths). Insufficient drilling has been completed at Dark Horse to

determine orientation of the mineralized zones and therefore true widths cannot be determined at this time. Exploration drill holes are

typically oriented normal to (at a right angle to) the trend of potential mineralized targets and holes dips range from 45 to 75 degrees.

2 Reported grades for intervals are weighted averages based on length of sampling intervals, typically 1 to 2 m etres. No top cut has

been applied; however, intervals greater than 10 g/t gold are reported separately for clarity.

Note: Exploration holes AAD -69, AAD-71, AAD-72 and AAD -73 intersected anomalous gold and/or zones anomalous in pathfinder

elements (arsenic, molybdenum and antimony) but no significant intervals greater than 0.3 g/t gold.

Three holes (AAD-65, AAD-66 and AAD -67) were drilled across the northern portion of

the Dark Horse prospect . AAD-65 and 66 were collared 290 metres and 160 metres,

respectively, north-northeast of previously reported hole AAD-61 (130 metres of 0.5 g/t

gold). Both holes intersected multiple gold-bearing zones, including intersections of 14

metres of 1.3 g/t gold and 20 metres of 1.7 g/t gold in AAD-66 and up to 59 g/t silver over

1 metre in AAD-65. Mineralization in both holes is hosted within pervasively clay altered

and brecciated volcanoclastic rocks with varying degrees of oxidation in the form of

hematite, limonite and g oethite. AAD-67 was drilled 260 metres south of AAD -61 and

returned relatively narrow anomalous gold zones within thick intervals of pervasively clay

altered and hydrothermally brecciated volcanic sequences . These three holes have

successfully demonstrated continuity of mineralization along the north -south strike ,

indicating the Dark Horse structure as a preferred fluid conduit with an interpreted pinch

and swell pattern common to many structurally controlled epithermal systems.

Ten widely spaced holes have now been drilled along a 1.2-kilometre portion of the N-S

structure. The holes have an average spacing of 160 metres apart (ranging from 42 to

255 metres) with an average vertical depth of 155 metres with the deepest hole (AAD-57)

drilling to a depth of 242 metres vertically and exhibiting strong gold mineralization over

the lower 100 metres of the hole. Drilling in early Q1-2021 focused on the northern portion

(north of AAD -57) of the Dark Horse structure , recognizing that the southern portion of

the Dark Horse structure hosting previously reported discovery holes AAD-58 (45m of 6

g/t gold) and AAD-57 (45m of 1.2 g/t gold) will be subject to close-spaced drilling during

the next round of drilling, now underway.

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Scout drilling outside the main N-S Dark Horse structure (holes AAD-68 to AAD-70, and

AAD-72 to ADD -73) focused on testing geophysical and geochemical soil anomalism

within the general Dark Horse prospect area . These holes confirmed widespread and

pervasive hydrothermal alteration, brecciation and mineralization within the wider Dark

Horse prospect area. Zones of anomalous gold mineralization in conjunction with key

indicator element anomalism, hydrothermal alteration , silicification and prospective

volcanoclastic-brecciated geology suggest the Dark Horse prospect is located in an

environment capable of hosting a major mineralizing event . These concepts will be

followed up in future drilling.

Drill Program – Q2-2021 Exploration

Core from the first 1,110 metres of drilling has been transported to SGS Laboratories,

Ulaanbaatar for analysis . Assay results are expected to be announced in the coming

weeks.

Geophysical Modelling and Interpretation

The Dark Hose area’s 2D and 3D geophysical modelling serves as an important targeting

tool and structural lineation mapping tool. Magnetics appear to support a relationship

between magnetic low signatures and zones of magnetite destructive clay alteration,

which have been shown to host anomalous gold mineralization. Induced polarization (IP)

also serves as an important targeting tool at Dark Horse as high concentrations of

disseminated sulphide minerals have been locally observed in drill core coincident with

intervals of elevated gold.

Geophysical modelling, interpretation and targeting are ongoing as we continue to

understand the larger Dark Horse system and its relationship to the Bayan Khundii system

to the south. Further geophysical surveys are planned for the 2021 field season to aid in

exploration success.

Clay Alteration and Short-Wave Infrared (SWIR) analysis

The presence of low -temperature argillic clay assemblages at Dark Horse sugge sts

formation within the upper stratigraphic levels (less than 150 metres) of an epithermal

system. Similar to Bayan Khundii, Dark Horse is dominated by illite clay alteration.

However, the presence of both smectite and kaolinite at Dark Horse indicates a lower

temperature environment consistent with the near -surface regions of an epithermal

system. These clay minerals are absent at Bayan Khundii, which has been interpreted to

have formed at greater than 150 metres depth. If Dark Horse represents the upper part

of a hydrothermal system, then the potential for zones of high-grade mineralization exists

at depth. This theory is further supported by the presence of vuggy/residual silica bodies

near AAD-57 and AAD-58, which may represent remnant near-surface lithocap zones.

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Fault Hosted Epithermal Model

The North-South structural feature at Dark Horse is best defined on the magnetic survey

map (see plan maps below), as are numerous zones of intersection between northeast

and northwest -trending cross st ructures and splays. Structural interpretations suggest

that the N-S trending structure is associated with dilation zones formed during t ectonic

compression from the south-southwest (Kloppenburg 2017). The resulting dilation zones

produced conduits for hydrothermal fluid channelling and subsequent alteration and

mineralization. Continued understanding of the prospect’s structural framework will be

key in further identifying zones of mineralization at Dark Horse and within the Khundii

tenements.

Bayan Khundii Gold Project Employment Orientation Program

In late 2020 , Erdene began developing a series of training and community outreach

programs as part of the Bayan Khundii Gold Project ’s construction readiness . These

programs include the company’s employment orientation, internship, and vocational

training opportunities, initially targeting local residents in the sub -province and province.

In March 2021, Erdene launched its employment orientation program with local residents

at its Bayan Khundii Gold Project site. Led by Erdene’s Mongolian management and

HSEC team, the five-day orientation covered the key topics of mine development,

community health and safety, environmental management, and local stakeholder

engagement through a combination of individual and team-based methods. To date, 36

people attended the orientation as a result of which all of whom identified a personal

development plan linked to the proposed mine operation. Given the strong interest and

active participation in the program, the company plans to re-start the program as soon as

COVID-19 restrictions allow.

Erdene expects the Project to provide direct employment for approximately 500

individuals during construction and as many as 400 during peak operation. The Bayan

Khundii Gold Project is expected to be come the largest employer in Bayankhong or

Province and to generate over US$100 million in profit tax and royalty for the Government

of Mongolia over the life of mine.

Mongolia COVID-19 Update

With the confirmation of the first community transmission of COVID-19 in November 2020,

the Government o f Mongolia implemented a series of restrictions on the movement of

people and delivery of goods and services. While restrictions were temporarily eased in

mid-Q1 2021 , preventive measures prohibiting certain business and public activities

remain in place in Ulaanbaatar, the country’s capital, and much of the country’s territory,

where there has been a recent increase in the number of reported cases. Additionally, in

March 2021, Bayankhongor Province, where Erdene’s Projects are located, reported its

first confirmed case of community transmission of COVID-19, imposing restrictions on the

movement of people within and to/from the province . In response, Erdene provided

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emergency funding assistance to the Bayankhongor Emergency Commission to support

its efforts to contain the spread of COVID-19 within the province.

Since mid -2020, Erdene has implemented operational changes to ensure the safety and

productivity of its people. In the field, daily health and safety briefings, body temperature

checks, enhanced hygiene protocols, rapid testing, and additional personal protective

equipment have been instituted. The company maintains a dedicated, registered nurse at site

with the capability to administer COVID-19 testing. With these measures, our team safely and

successfully completed the Q1 2021 Dark Horse Scout drilling program and launched a follow

up exploration program in late March 2021. The Company’s corporate and administrative

teams continue to work modified schedules and have adopted enhanced hygiene measures

that allow operations to continue without significant disruption.

Though the impact of COVID-19 on the Company’s operations has been modest to date, the

COVID-19 pandemic continues to evolve. The Company will monitor the impact of COVID -

19 on its operations in 2021, particularly potential disruptions to the Bayan Khundii Gold

Project schedule or budget, prior to reaching a construction decision, which is expected in

mid-2021.

The Company extends its appreciation to all medical, public safety, and essential workers for

their efforts to safeguard public health and help prevent the spread of COVID-19 in Mongolia

and Canada.

Khundii Gold District

Erdene’s deposits are located in the Edren Terrane, within the Central Asian Orogenic Belt,

host to some of the world’s largest gold and copper -gold deposits. The Company has been

the leader in exploration in southwest Mongolia over the past decade and is responsible for

the discovery of the Khundii Gold District comprised of multiple high-grade gold and gold/base

metal prospects, two of which are being considered for development: the 100%-owned Bayan

Khundii and Altan Nar projects. Together, these deposits comprise the Khundii Gold Project.

The Bayan Khundii Gold Resource1 includes 521,000 ounces of 3.16 g/t gold Measured and

Indicated (“M&I”)² and 103,000 ounces of Inferred resources at 3.68 g/t gold. Within the M&I

resource, a proven and probable open -pit reserve totals 409,000 ounces at 3.7 g/t (see the

full press release here), providing significant potential growth of reserves with the

development of the remaining M&I and Inferred resources2.

In July 2020, Erdene announced the results of an independent Feasibility Study for the Bayan

Khundii Gold Project (press release here). The Feasibility Study results include an after -tax

Net Present Value at a 5% discount rate and a US$1,400/oz gold price of US$100 million and

Internal Rate of Return (“IRR”) of 42%. The Feasibility Study envisions an open -pit mine at

Bayan Khundii, producing an average of 63,500 oz gold per year, for seven years, at a head

grade of 3.71 g/t gold, utilizing a conventional carbon in pulp processing plant. Production is

expected to commence in early 2022 based on the current project schedule.

1 For details of the Mineral Resources see Khundii Gold Project NI 43-101 Technical Report, Tetra Tech December 4,

2019 – SEDAR

2 M&I: 171,000 ounces of 3.77 g/t gold Measured, and 349,700 ounces of 2.93 g/t gold Indicated

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Erdene Resource Development Corp. is a Canada-based resource company focused on the

acquisition, exploration, and development of precious and base metals in underexplored and

highly prospective Mongolia. The Company has interests in three mining licenses and two

exploration licenses in Southwest Mongolia, where exploration success has led to the

discovery and definition of the Khundii Gold District. Erdene Resource Development Corp. is

listed on the Toronto and the Mongolian stock exchanges. Further information is available at

www.erdene.com. Important information may be disseminated exclusively via the website;

investors should consult the site to access this information.

Qualified Person and Sample Protocol

Peter Dalton, P.Geo. (Nova Scotia), Senior Geologist for Erdene, is the Qualified Person as

that term is defined in National Instrument 43 -101 and has reviewed and approved the

technical information contained in this news release. All samples have been assayed at SGS

Laboratory in Ulaanbaatar, Mongolia. In addition to internal checks by SGS Laboratory, the

Company incorporates a QA/QC sample protocol utilizing prepared standards and blanks. All

samples undergo standard fire assay analysis for gold and ICP -OES (Inductively Coupled

Plasma Optical Emission Spectroscopy) analysis for 33 additional elements. For samples that

initially return a grade greater than 5 g/t gold, additional screen -metallic gold analysis is

carried out which provides a weighted average gold grade from fire assay analysis of the

entire +75 micron fraction and three 30 -gram samples of the -75 micron fraction from a 500

gram sample.

Erdene’s drill core sampling protocol consisted of collection of samples over 1 or 2 metre

intervals (depending on the lithology and style of mineralization) over the entire length of the

drill hole, excluding minor post -mineral lithologies and un -mineralized granitoids. Sample

intervals were based on meterage, not geological controls or mineralization. All drill core was

cut in half with a diamond saw, with half of the core placed in sample bags and the remaining

half securely retained in core boxes at Erdene’s Bayan Khundii exploration camp. All samples

were organized into batches of 30 including a commercially prepared standard, blank and

either a field duplicate, consisting of two quarter -core intervals, or a laboratory duplicate.

Sample batches were periodically shipped directly to SGS in Ulaanbaatar via Erdene’s

logistical contractor, Monrud Co. Ltd.

Forward-Looking Statements

Certain information regarding Erdene contained herein may constitute forward -looking

statements within the meaning of applicable securities laws. Forward-looking statements may

include estimates, plans, expectations, opinions, forecast s, projections, guidance or other

statements that are not statements of fact. Although Erdene believes that the expectations

reflected in such forward -looking statements are reasonable, it can give no assurance that

such expectations will prove to have bee n correct. Erdene cautions that actual performance

will be affected by a number of factors, most of which are beyond its control, and that future

events and results may vary substantially from what Erdene currently foresees. Factors that

could cause actual results to differ materially from those in forward-looking statements include

the ability to obtain required third party approvals, market prices, exploitation and exploration

results, continued availability of capital and financing and general economic, market or

business conditions. The forward-looking statements are expressly qualified in their entirety