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Erdene Continues to Outline Ulaan Feeder Zone, Intersects 27 Metres of 3.5 G/T GOLD, Including 2 Metres of 24.9 G/T GOLD

Drill Results

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ERDENE CONTINUES TO OUTLINE ULAAN FEEDER ZONE,

INTERSECTS 27 METRES OF 3.5 G/T GOLD, INCLUDING 2 METRES

OF 24.9 G/T GOLD

Press Release

Halifax, Nova Scotia

2022.07.26

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

“Company”) is pleased to announce final results from the Q2 2022 drill program at Ulaan

Southeast (“Ulaan SE”), located 300 metres west of the construction ready Bayan Khundii

Gold Project in southwest Mongolia. This program expanded known mineralization at the

Ulaan SE discovery to the west and at depth, and intersected an interpreted high-grade,

gold bearing “feeder” structure. Follow-up exploration at Ulaan SE is currently underway.

Highlights

• UDH-53 returned high-grade mineralization within a projected feeder zone, including

2 metres of 24.9 g/t gold within 27 metres of 3.47 g/t gold

• UDH-52, 60 metres SSE of UDH-53, intersected a wide zone of mineralization – 189

metres averaging 0.8 g/t gold

• Mineralization at Ulaan SE has been traced over a 200 metre strike, to a depth of 450

metres, that remains open to the west and at depth; highlights of Q2 drilling include:

o UDH-35 included the highest average grade intersection to date at Ulaan SE

▪ Intersected 23 metres of 13.7 g/t gold within 41 metres of 8.1 g/t gold,

beginning 187 metres downhole

o UDH-21, including the hole extension, returned one of the thickest gold zones

in the Khundii District

▪ Intersected 335 metres of 1.1 g/t gold, beginning 115 metres downhole,

ending in mineralization

▪ Includes 27 metres of 8.7 g/t gold, within 77 metres of 3.2 g/t gold

o UDH-36 intersected 179 metres of 1.2 g/t gold, beginning 72 metres downhole

▪ Includes several one-metre, high-grade intersections, ranging from 10-

33 g/t gold, and ending in mineralization at 350 metres

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Quotes from the Company

“Ulaan drilling has returned very high grade zones in the feeder structure as well as

exceptionally thick zones of mineralization, exceeding 300 metres, which remain open, in

the core of the discovery,” said Peter Akerley, Erdene’s President and CEO. “This newest

Khundii District discovery is interpreted as the western extension of the Bayan Khundii

deposit, demonstrating the resource expansion potential from deeper exploration in the

District.”

“In the past week, we launched a follow-up exploration program. The outcome of this

program, as well as the results from the recently completed regional reverse-circulation

(“RC”) program, will focus our exploration work for the balance of 2022 ,” continued Mr.

Akerley. “We are confident that we are well on our way to achieving our two million ounce

gold equivalent resource target by the end of the year.”

Summary of Drill Results

The primary objectives of the Q2 2022 Ulaan SE drilling program were to test interpreted

high-grade feeder zones along bounding or intersecting structures in the northern portion

of the Ulaan SE discovery, and to test mineralization at depth.

Six new holes, as well as five hole-extensions, totaling 2,463.7 metres, were completed

as part of the Q2 2022 Ulaan SE drilling program. Results are summarized below in Table

1. Results for the final two holes in the program, UDH-52 and UDH-53, are newly reported;

all other results were reported on June 6, 2022.

The Q2 2022 program at Ulaan SE confirmed a zone of high -grade mineraliza tion

interpreted to be associated with intersecting or bounding structures and possibly a feeder

zone. Drill hole UDH-35 returned the highest average grade interval intersection to date

at Ulaan SE, with 41 metres of 8.1 g/t gold starting 187 metres downhole. Drill hole UDH-

36 extended high-grade mineralization further west from the discovery area, intersecting

one of the broadest zones of mineralization to date in Erdene’s Khundii Gold District. Hole

UDH-53 was drilled to confirm extension of the feeder z one at depth and intersected 27

metres of 3.47 g/t gold, including three one-metre intervals greater than 10 g/t gold (up to

35.5 g/t gold), and ended in mineralization.

Step-out drill holes and hole extensions continue to expand the area o f known

mineralization, which remains open to the west and at depth. Drillhole UDH-37 intersected

the targeted gold mineralized tuffaceous host lithology, broadening the potential for gold

mineralization as exploration progresses westward further into the core of the Ulaan

license area. UDH-38 complimented the results of UDH-37, extending gold mineralization

westward; however, this drillhole also indicates shallower gold mineralization, with gold

mineralization beginning 42 metres down hole.

Hole extensions (an additional 100 to 200 metres, to total depths of 350 to 450 metres )

demonstrated that gold mineralization extends over 400 metres vertically. Mineralization

remains open at de pth with two of the holes extended to 450 metres end ing in

mineralization.

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Table 1: Ulaan Q2 2022 Drilling Highlights

(Intervals averaging over 0.30 g/t gold)

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

Newly Reported Drill Holes

UDH-52 86 275(2) 189 0.80

UDH-53 248 337(2) 89 1.40

Incl 248 275 27 3.47

Incl 248 250 2 24.90(5)

Incl 295 296 1 11.88

Previously Reported Q2 – 2022 Drill Holes

UDH-35 107 116 9 0.49

And 176 178 2 0.46

And 187 228 41 8.10

Incl 188 211 23 13.73

Incl 188 189 1 10.87

Incl 197 198 1 44.40

Incl 208 211 3 68.32

Incl 208 209 1 108.12

And 235 238 3 0.36

And 246 251(2) 5 0.34

UDH-36 2 4 2 0.51

And 72 251(2) 179 1.23

Incl 106 107 1 15.52

Incl 142 143 1 14.36

Incl 146 147 1 10.84

Incl 227 228 1 33.43

UDH-37 64 68 4 0.44

And 168 272 104 0.31

Incl 202 246 44 0.51

UDH-38 42 68 26 0.30

And 193 262 69 0.48

And 346 348 2 0.56

Hole Extensions

UDH-08 20 22 2 0.44(3)

And 202 206 4 0.37

UDH-12 310 314 4 0.36

And 324 328 4 0.46

And 338 340 2 0.58

UDH-17 287 289 2 1.71(3)

And 314 368 54 1.55(4)

Incl 348 350.3 2.3 21.57(3)

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

And 412 422 10 0.33

And 425 426 1 0.39

And 432 434 2 0.30

UDH-21 115 450.3(2) 335.3 1.10(4)

Incl 115 192 77 3.19(3)

Incl 131 158 27 8.74(3)

Incl 139 140 1 156.54(3)

Incl 155 156 1 20.98(3)

Incl 209 280 71 0.81(3)

Incl 222 230 8 1.92(3)

Incl 257 271 14 2.79(3)

Incl 304 318 14 0.34(3)

Incl 342 450.3(2) 108.3 0.53(4)

Incl 417 450.3(2) 33.3 0.91

UDH-28 282 291 9 0.47(3)

And 306 356 50 0.47(4)

And 370 384 14 0.37

And 394 450(2) 56 0.34

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

mineralization and true thicknesses

2. End of hole

3. Previously reported interval (2021)

4. Extended interval

5. Included two, one-metre intervals, both greater than 10 g/t gold (14.3 and 35.5 g/t gold)

Next Steps

The results to date demonstrate a broad and thick zone of mineralization over a vertical

depth in excess of 400 metres, that remains open at depth and to the west. Analysis of

multi-element geochemical data, complimented by downhole magnetic susceptibility

readings, are introducing correlations previously unrecognized at Ulaan SE. These

datasets indicate that i ncreased potassium concentrations ( after pervasive adularia-

Kspar alteration) in conjunction with low magnetic susce ptibility readings, are strongly

correlated with the targeted gold bearing tuffaceous host package. 3D modelling of these

combined variables will serve as important target vectoring tools for future drilling at Ulaan

SE. A follow -up drilling program has be en designed to further test continuation of

mineralization to the west and at depth, including further tracing of the high -grade

mineralization identified to date which has been interpreted as a potential structurally

controlled feeder zone.

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Ulaan SE Overview

The Ulaan SE gold target is a blind-top discovery identified in Q3 2021. The prospect is

characterized by hundreds of metres of gold mineralization (up to 354 metres

continuously in a single drill hole ) over an area 200 metres by 250 metres. Gold

mineralization begins approximately 80 metres from surface and remains open along

strike to the west/northwest and at depth. Intervals include 152 metres of 1.7 g/t gold in

UDH-22 (from 85 metres) and 77 metres of 3.2 g/t gold in UDH-21 (from 115 metres), as

well as the more recent results noted in this release. Similar to the B ayan Khundii gold

deposit, approximately 300 metres east, the mineralizing event is characterized by

exceptionally high -grade quartz ± hematite and adularia veins and stockwork zones

enveloped by the same gold bearing, silicified, white-mica altered lapilli tuff sequence.

The southern portion of the Ulaan license has areas of anomalous gold -in-soil over an

area 3.5 kilometres by 1 kilometre. The underlying geology and alteration appears to be

analogous to the gold mineralization at Ulaan Southeast and Bayan Khundii, namely

tuffaceous units with white mica and silica alteration. A series of holes have been drilled

to test high priority targets , for which the re sults are pending and expected in early Q3

2022.

Khundii Minerals District

Erdene’s deposits are in the Trans Altai 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 so uthwest Mongolia over the past decade and is

responsible for the discovery of the Khundii Gold District comprised of multiple high-grade

gold and base metal prospects, one of which is currently being developed, the 100% -

owned Bayan Khundii Gold Project, an d another which is being considered for

development, the 100% -owned Altan Nar Project. In 2021, the Company identified two

new significant gold prospects, Dark Horse and Ulaan Southeast.

The Bayan Khundii Gold Resource 1 includes 585,100 ounces of 2.19 g/t gold Measured

and Indicated (“M&I”) 2 and 35,900 ounces of Inferred resources at 2.18 g/t gold. Within

the M&I resource, a Proven and Probable open -pit reserve totals 409,000 ounces at 3.7

g/t gold3 (press release here), providing significant potential for reserves growth with the

development of the remaining M&I and Inferred resources1.

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

1 For details of the Mineral Resources see Erdene’s Q2/2021 results press release, dated August 16, 2021, and the

Company’s Q2 2021 MD&A, available on the Company’s website or SEDAR.

2 M&I: 232,700 ounces of 2.39 g/t gold Measured and 352,400 ounces of 2.08 g/t gold Indicated

3 P&P: 165,000 ounces of 4.4 g/t gold Proven and 256,000 ounces of 3.4 g/t gold Probable; For details of the Mineral

Reserves see Khundii Gold Project NI 43 -101 Technical Report, Tetra Tech December 4, 201 9 available on the

Company’s website or SEDAR

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US$100 million and Internal Rate of Retur n (“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 2023 based on the current

project schedule.

About Erdene

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

the acquisition, exploration, and development of precio us and base metals in

underexplored and highly prospective Mongolia. The Company has interests in three

mining licenses a nd an exploration license 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 informati on 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 protoc ol utilizing prepared

standards and blanks. All samples undergo standard fire assay analysis for gold and ICP-

OES (Induct ively Coupled Plasma Optical Emission Spectroscopy) analysis for 33

additional elements. For samples that initially return a grade grea ter 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.

Reported intervals are apparent thicknesses, i.e. downhole widths. The current Ulaan drill

holes are all dipping at 85 degrees and oriented to intersec t SW dipping WNW trending

gold bearing veins. Additional study is required to confirm true widths. Reported grades

for intervals are weighted averages based on length of sampling intervals. No top cut has

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been applied; however, all intervals greater than 10 g/t gold and 100 g/t gold are reported

individually for clarity

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, forecasts, 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 been correct. Erdene ca utions 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 substa ntially from what Erdene

currently foresees. Factors that could cause actual results to differ m aterially from those

in forward-looking statements include the ability to obtain required third party approvals,

market prices, exploitation, and exploration re sults, continued availability of capital and

financing and general economic, market or business conditions. The forward -looking

statements are expressly qualified in their entirety by this cautionary statement. The

information contained herein is stated as of the current date and is subject to change after

that date. The Company does not assume the o bligation to revise or update these

forward-looking statements, except as may be required under applicable securities laws.

NO REGULATORY AUTHORITY HAS APPROVE D OR DISAPPROVED THE

CONTENTS OF THIS RELEASE

Erdene Contact Information

Peter C. Akerley, President and CEO, or

Robert Jenkins, CFO

Phone: (902) 423-6419

Email: [email protected]

Twitter: https://twitter.com/ErdeneRes

Facebook: https://www.facebook.com/ErdeneResource

LinkedIn: https://www.linkedin.com/company/erdene-resource-development-corp-/

20 km

Landsat 8 True Colour

N

Shallow, High-Grade, Gold and Polymetallic Deposits and Prospects

Exploration License

Mining License

Prospect

Deposit

Au

Cu

Mo

Bayan Khundii Gold Deposit

Shovel ready high-grade,

open-pit gold project

Ulaan SE Gold Discovery

Blind top gold discovery

(July/21)

Dark Horse Gold Discovery

High-grade, near surface gold

discovery (Jan/21)

Gold polymetallic deposit

Target >1Moz of Au Eq>2g/t

Altan Nar Gold Deposit

Zuun Mod Moly & Copper Deposit

Largest, undeveloped, advanced stage

molybdenum-copper project in Asia

1

KHUNDII MINERALS DISTRICT – MULTI-MILLION OUNCE POTENTIAL

Four Gold Discoveries, Molybdenum Copper Deposit & Multiple High-Priority Targets