Iamgold Releases High Grade Infill Drill Results at the Diakha-Siribaya GOLD Project IN Mali

NEWS RELEASE

TSX: IMG NYSE: IAG

IAMGOLD RELEASES HIGH GRADE INFILL DRILL RESULTS AT

THE DIAKHA-SIRIBAYA GOLD PROJECT IN MALI

Toronto, Ontario, November 30, 2021 – IAMGOLD Corporation (“IAMGOLD” or the “Company”) is pleased to

announce results from its 2021 exploration infill drilling program completed at the Diakha deposit on its wholly

owned Diakha-Siribaya Gold project located in western Mali along the borders with Senegal and Guinea.

Highlights include:

Diamond Drill Holes (refer to Table 1 below)

 12 meters (“m”) at 9.32 grams per tonne gold (“g/t Au”) in drill hole SRD21-284 from 284 m including

o 3 m at 27.15 g/t Au from 284 m

 13 m at 11.20 g/t Au in drill hole SRD21-303 from 277 m including

o 2 m at 67.98 g/t Au from 279 m

 10 m at 11.70 g/t Au in drill hole SRD21-305 from 164 m including

o 4 m at 27.63 g/t Au from 169 m

 17 m at 2.17 g/t Au in drill hole SRD21-300 from 177 m, followed by a separate interval of:

o 20 m at 5.47 g/t Au from 269 m including

o 7 m at 11.74 g/t Au from 282 m

 20 m at 5.40 g/t Au in drill hole SRD21-308 from 108 m including

o 1 m at 69.34 g/t Au from 114 m

 13 m at 4.12 g/t Au in drill hole SRD21-307 from 224 m including

o 1 m at 17.40 g/t Au from 225 m and

o 2 m at 13.40 g/t Au from 233 m

 15 m at 3.91 g/t Au in drill hole SRD21-311 from 242 m including

o 3 m at 13.06 g/t Au from 246 m and

o 1 m at 11.40 g/t Au from 251 m

Reverse Circulation (“RC”) Drill Holes (refer to Table 2 below)

 16 m at 14.00 g/t Au in drill hole SRD21-891 from 89 m including

o 3 m at 41.95 g/t Au from 99 m

 20 m at 1.97 g/t Au in drill hole SRD21-883 from 43 m, including

o 1 m at 21.89 g/t Au from 48 m, followed by a separate interval of:

o 27 m at 2.12 g/t Au from 75 m including

o 3 m at 6.52 g/t Au from 76 m and

o 1m at 21.31 g/t Au from 101 m

 12 m at 4.19 g/t Au in drill hole SRD21-889 from 108 m including

o 2 m at 18.84 g/t Au from 117 m

 32 m at 1.97 g/t Au in drill hole SRD21-907 from 88 m including

o 1 m at 16.40 g/t Au from 89 m

 11 m at 4.96 g/t Au in drill hole SRD21-848 from 55 m including

o 1 m at 39.80 g/t Au from 65 m

 24 m at 2.23 g/t Au in drill hole SRD21-882 from 43 m including

o 2 m at 17.01 g/t Au from 54 m

Page | 2 of 14

Craig MacDougall, Executive Vice President, Growth for IAMGOLD, stated: "We are very pleased with the results

of our 2021 exploration program, which have helped to demonstrate continuity of mineralizatio n between

previously completed drill holes and better delineate the distribution and controls on high grade mineralized

structures within the known resource.”

“The data from this program will help improve the current deposit model and support the completion of an updated

mineral resource s estimation as we continue to advance towards our objective of increasing total indicated

resources to above 1.5 million ounces.”

In 2021, the Company completed a combined 19,952 meters in 131 diamond and RC drill holes with 22,328 assay

samples (including QA/QC samples) submitted for analysis. The main objective of the drilling program was to infill

and increase confidence in the current resources estimate for the Diakha deposit.

Diakha-Siribaya Gold Project

The Diakha-Siribaya project is wholly -owned by IAMGOLD and consists of eight contiguous exploration permits

which cover a total area of 596.5 square kilometres, located in the Kédougou -Kéniéba inlier of the West African

Craton region of western Mali along the borders with Senegal and Guinea.

Gold mineralization is hosted within highly prospective, Birimian -aged metasedimentary, volcanic and intrusive

rocks proximal to the Senegal -Mali Shear Zone. At Diakha, the largest deposit discovered to date, gold

mineralization occur s within an albitized sandstone unit similar to that hosting IAMGOLD's Boto Gold deposit

located approximately 10 kilometres to the north along strike.

The current mineral resources estimate for the Diakha deposit (on a 100% basis using a $1,500 per ounce gold

price) comprises 15.9 million tonnes of indicated resources averaging 1.20 grams of gold per tonne for 615,300

ounces of gold and 18.2 million tonnes of inferred resources averaging 1.62 grams of gold per tonne for 947,500

ounces (see news releases dated January 30, 2019 and February 17, 2021).

Next Steps

The drilling data from the 2021 exploration program is currently being incorporated into a revised deposit model

to support the completion of an updated mineral resource s estimate targeted for comple tion in the first half of

2022.

Figure 1 – Diakha-Siribaya – Diakha deposit drill hole surface plan and highlighted 2021 assays

Page | 3 of 14

Figure 2 – Diakha-Siribaya – Diakha deposit longitudinal section and highlighted 2021 assay results

Table 1 - Diakha Drilling Results - 2021 Diamond Drilling Program

Hole No. UTM WGS84 Zone 29N AZ DIP EOH From To Core

Interval (1) Au (2)

Easting Northing Elevation (°) (°) (m) (m) (m) (m) (g/t)

SRD21-275 240663 1369113 158 113 -58 320.0 163.0 165.0 2.0 3.33

196.0 214.0 18.0 1.51

including 201.0 205.0 4.0 3.94

267.0 270.0 3.0 6.54

including 268.0 270.0 2.0 9.04

SRD21-276 240660 1369062 161 115 -52 301.0 134.0 137.0 3.0 0.80

252.0 256.0 4.0 6.98

including 255.0 256.0 1.0 18.57

SRD21-277 240670 1369218 161 115 -59 350.0 152.0 155.0 3.0 17.89

including 153.0 154.0 1.0 50.15

SRD21-278 240622 1369134 157 115 -59 270.0 214.0 223.0 9.0 9.16

including 216.0 217.0 1.0 23.10

including 219.0 223.0 4.0 11.82

SRD21-279 240583 1369100 156 115 -55 323.0 303.0 305.0 2.0 3.10

SRD21-280 240598 1369254 158 115 -61 320.0 277.0 282.0 5.0 3.71

SRD21-281 240586 1369205 158 115 -60 338.1 291.0 294.0 3.0 2.27

SRD21-282 240642 1369293 160 115 -59 295.5 171.0 174.0 3.0 3.54

SRD21-283 240757 1369071 169 115 -58 218.0 143.0 151.0 8.0 8.15

Page | 4 of 14

Table 1 - Diakha Drilling Results - 2021 Diamond Drilling Program

Hole No. UTM WGS84 Zone 29N AZ DIP EOH From To Core

Interval (1) Au (2)

Easting Northing Elevation (°) (°) (m) (m) (m) (m) (g/t)

including 144.0 147.0 3.0 10.57

including 148.0 151.0 3.0 10.81

157.0 162.0 5.0 1.33

197.0 207.0 10.0 1.04

SRD21-284 240718 1369254 163 115 -61 325.0 203.0 207.0 4.0 2.26

including 206.0 207.0 1.0 6.20

226.0 233.0 7.0 2.01

including 226.0 227.0 1.0 9.22

239.0 252.0 13.0 1.72

including 250.0 252.0 2.0 8.35

284.0 296.0 12.0 9.32

including 284.0 287.0 3.0 27.15

303.0 305.0 2.0 6.89

SRD21-285 240691 1368948 159 115 -49 240.0 46.0 48.0 2.0 1.21

170.0 183.0 13.0 1.92

including 176.0 180.0 4.0 4.46

198.0 206.0 8.0 1.75

including 200.0 201.0 1.0 4.21

223.0 225.0 2.0 0.55

SRD21-286 240765 1369234 165 115 -60 255.0 23.0 26.0 3.0 0.87

124.0 128.0 4.0 2.20

134.0 149.0 15.0 1.22

including 138.0 139.0 1.0 7.41

217.0 225.0 8.0 1.42

SRD21-287 240684 1368614 157 115 -61 160.0 148.0 151.0 3.0 0.89

SRD21-288 240968 1369139 194 115 -70 200.0 50.0 54.0 4.0 0.55

177.0 186.0 9.0 2.33

including 177.0 179.0 2.0 5.98

196.0 199.0 3.0 0.93

SRD21-289 240794 1368833 166 115 -54 140.0 73.0 75.0 2.0 1.86

112.0 116.0 4.0 0.96

SRD21-290 240875 1369291 170 115 -64 155.0 36.0 40.0 4.0 0.98

66.0 68.0 2.0 0.86

85.0 90.0 5.0 2.73

SRD21-291 240769 1368902 178 115 -50 187.8 61.0 63.0 2.0 1.20

SRD21-292 240934 1369095 203 115 -63 220.0 33.0 52.0 19.0 1.09

SRD21-293 240774 1368954 183 115 -76 207.5 29.0 36.0 7.0 2.75

including 30.0 31.0 1.0 13.62

133.0 150.0 17.0 2.75

including 133.0 134.0 1.0 5.56

Page | 5 of 14

Table 1 - Diakha Drilling Results - 2021 Diamond Drilling Program

Hole No. UTM WGS84 Zone 29N AZ DIP EOH From To Core

Interval (1) Au (2)

Easting Northing Elevation (°) (°) (m) (m) (m) (m) (g/t)

including 145.0 146.0 1.0 6.78

SRD21-294 240956 1369031 205 115 -63 181.0 104.0 111.0 7.0 2.36

including 109.0 110.0 1.0 7.31

150.0 168.0 18.0 1.88

including 154.0 158.0 4.0 5.50

SRD21-295 240994 1369347 177 115 -68 169.8 113.0 116.0 3.0 2.55

SRD21-296 240844 1369193 173 115 -59 180.0 89.0 95.0 6.0 0.70

SRD21-297 241004 1369452 175 115 -66 180.0 35.0 37.0 2.0 2.85

52.0 56.0 4.0 0.87

117.0 119.0 2.0 0.98

SRD21-298 240844 1369253 171 115 -51 184.6 95.0 97.0 2.0 1.93

102.0 112.0 10.0 1.18

including 104.0 105.0 1.0 8.55

SRD21-299 240840 1369527 164 115 -60 180.0 1.0 3.0 2.0 0.70

21.0 25.0 4.0 0.70

80.0 90.0 10.0 1.04

123.0 125.0 2.0 1.99

136.0 140.0 4.0 2.51

including 137.0 138.0 1.0 6.00

SRD21-300 240738 1369301 163 115 -58 298.0 58.0 63.0 5.0 1.53

177.0 194.0 17.0 2.17

including 178.0 180.0 2.0 6.40

including 191.0 192.0 1.0 6.85

269.0 289.0 20.0 5.47

including 277.0 278.0 1.0 11.67

including 282.0 289.0 7.0 11.74

294.0 298.0 4.0 0.86

SRD21-301 240754 1369539 161 115 -55 180.0 7.0 10.0 3.0 0.72

75.0 78.0 3.0 1.54

178.0 180.0 2.0 5.23

SRD21-302 240739 1369520 161 115 -64 280.0 30.0 32.0 2.0 0.60

78.0 86.0 8.0 0.63

94.0 96.0 2.0 1.62

104.0 111.0 7.0 0.65

234.0 236.0 2.0 0.73

267.0 271.0 4.0 0.76

SRD21-303 240698 1369321 161 115 -65 366.4 277.0 290.0 13.0 11.20

including 279.0 281.0 2.0 67.98

323.0 333.0 10.0 1.83

including 327.0 328.0 1.0 10.40

Page | 6 of 14

Table 1 - Diakha Drilling Results - 2021 Diamond Drilling Program

Hole No. UTM WGS84 Zone 29N AZ DIP EOH From To Core

Interval (1) Au (2)

Easting Northing Elevation (°) (°) (m) (m) (m) (m) (g/t)

350.0 352.0 2.0 1.38

SRD21-304 240651 1369561 158 115 -61 390.7 2.0 5.0 3.0 0.70

60.0 62.0 2.0 0.68

119.0 121.0 2.0 1.89

184.0 204.0 20.0 0.81

208.0 210.0 2.0 1.08

224.0 227.0 3.0 1.53

340.0 344.0 4.0 3.05

350.0 371.0 21.0 1.79

including 353.0 354.0 1.0 22.49

SRD21-305 240735 1369329 162 115 -55 211.8 56.0 59.0 3.0 2.77

including 57.0 58.0 1.0 5.18

164.0 174.0 10.0 11.70

including 169.0 173.0 4.0 27.63

195.0 200.0 5.0 1.22

SRD21-306 240655 1369453 159 115 -62 390.0 228.0 246.0 18.0 0.55

309.0 312.0 3.0 0.63

339.0 341.0 2.0 3.28

SRD21-307 240763 1369453 163 115 -52 247.8 51.0 69.0 18.0 0.60

90.0 92.0 2.0 0.99

100.0 110.0 10.0 1.11

including 107.0 108.0 1.0 5.90

144.0 156.0 12.0 0.76

224.0 237.0 13.0 4.12

including 225.0 226.0 1.0 17.40

including 233.0 235.0 2.0 13.40

SRD21-308 240755 1369322 163 115 -55 184.8 91.0 102.0 11.0 0.58

108.0 128.0 20.0 5.40

including 114.0 115.0 1.0 69.34

143.0 152.0 9.0 1.03

173.0 180.0 7.0 1.33

SRD21-309 240742 1369352 162 115 -58 195.5 45.0 56.0 11.0 0.92

SRD21-310 240776 1369313 164 115 -55 170.0 16.0 18.0 2.0 0.72

76.0 98.0 22.0 2.07

including 76.0 79.0 3.0 8.49

SRD21-311 240735 1369630 161 115 -56 300.0 26.0 31.0 5.0 0.76

83.0 86.0 3.0 3.36

158.0 160.0 2.0 2.29

182.0 186.0 4.0 0.64

242.0 257.0 15.0 3.91

Page | 7 of 14

Table 1 - Diakha Drilling Results - 2021 Diamond Drilling Program

Hole No. UTM WGS84 Zone 29N AZ DIP EOH From To Core

Interval (1) Au (2)

Easting Northing Elevation (°) (°) (m) (m) (m) (m) (g/t)

including 246.0 249.0 3.0 13.06

including 251.0 252.0 1.0 11.40

263.0 267.0 4.0 1.44

SRD21-312 240937 1369535 172 115 -45 92.0 28.0 30.0 2.0 2.01

61.0 63.0 2.0 0.63

SRD21-313 240679 1369659 158 115 -61 371.0 13.0 15.0 2.0 1.44

120.0 122.0 2.0 2.72

133.0 135.0 2.0 1.94

142.0 148.0 6.0 2.25

235.0 257.0 22.0 0.59

280.0 285.0 5.0 18.73

304.0 306.0 2.0 6.27

SRD21-314 240848 1369643 162 115 -61 200.0 134.0 140.0 6.0 2.00

including 139.0 140.0 1.0 8.46

SRD21-315 240673 1369711 156 115 -56 360.6 111.0 119.0 8.0 0.62

152.0 154.0 2.0 7.44

250.0 255.0 5.0 8.41

286.0 289.0 3.0 1.20

SRD21-316 240616 1369743 154 114 -59 411.3 166.0 177.0 11.0 1.05

191.0 193.0 2.0 1.08

240.0 243.0 3.0 2.83

SRD21-317 240881 1369672 162 116 -69 180.0 67.0 76.0 9.0 4.22

including 75.0 76.0 1.0 21.25

127.0 130.0 3.0 3.84

140.0 144.0 4.0 1.51

Notes:

1. The true widths of intersections are unknown at this time, but are interpreted to approximate the reported downhole

lengths.

2. Drillhole intercepts are calculated using a minimum downhole length of two (2) meters, a cut-off grade of 0.5 g/t gold, and

may include up to four (4) metres of internal dilution.

3. Assays are reported uncut, but high grade sub-intervals are highlighted.

Table 2 - Diakha Drilling Results - 2021 RC Drilling Program

Hole No. UTM WGS84 Zone 29N AZ DIP EOH From To Core

Interval (1) Au (2)

Easting Northing Elevation (°) (°) (m) (m) (m) (m) (g/t)

SRC21-841 240799 1368401 164 115 -58 108 47.0 49.0 2.0 0.54

97.0 102.0 5.0 0.58

SRC21-842 240818 1368443 162 115 -59 84 37.0 40.0 3.0 1.07

47.0 51.0 4.0 1.18

Page | 8 of 14

Table 2 - Diakha Drilling Results - 2021 RC Drilling Program

Hole No. UTM WGS84 Zone 29N AZ DIP EOH From To Core

Interval (1) Au (2)

Easting Northing Elevation (°) (°) (m) (m) (m) (m) (g/t)

SRC21-843 240777 1368459 161 115 -59 142 33.0 41.0 8.0 0.99

115.0 124.0 9.0 1.04

SRC21-844 240748 1368410 166 115 -59 120 98.0 100.0 2.0 0.57

SRC21-845 No Significant results

SRC21-846 No Significant results

SRC21-847 240720 1368548 158 115 -53 150 76.0 87.0 11.0 0.98

97.0 99.0 2.0 0.93

140.0 142.0 2.0 1.14

SRC21-848 240764 1368528 159 115 -54 120 55.0 66.0 11.0 4.96

Including 65.0 66.0 1.0 39.80

80.0 83.0 3.0 0.82

SRC21-849 240730 1368593 158 115 -61 102 57.0 59.0 2.0 0.67

87.0 90.0 3.0 0.57

SRC21-850 No Significant results

SRC21-851 No Significant results

SRC21-852 240535 1368735 155 115 -60 108 72.0 75.0 3.0 0.54

82.0 84.0 2.0 1.39

SRC21-853 240531 1368791 153 115 -60 120 69.0 73.0 4.0 1.40

78.0 80.0 2.0 0.68

85.0 87.0 2.0 2.21

SRC21-854 240572 1368772 153 115 -60 84 56.0 58.0 2.0 1.49

66.0 68.0 2.0 2.86

SRC21-855 240508 1368855 152 115 -60 132 108.0 110.0 2.0 0.87

SRC21-856 240545 1368894 153 115 -60 114 52.0 54.0 2.0 11.41

62.0 68.0 6.0 0.58

SRC21-857 240524 1368962 153 115 -55 126 72.0 79.0 7.0 1.24

101.0 106.0 5.0 0.99

SRC21-858 240690 1368661 157 115 -61 146 137.0 145.0 8.0 1.54

Including 138.0 139.0 1.0 6.02

SRC21-859 240735 1368640 156 115 -58 96 44.0 52.0 8.0 1.02

74.0 78.0 4.0 7.49

Including 77.0 78.0 1.0 20.11

SRC21-860 240749 1368682 153 106 -59 102 32.0 52.0 20.0 0.95

70.0 72.0 2.0 1.80

SRC21-861 No Significant results

SRC21-862 240829 1368595 155 115 -61 78 59.0 74.0 15.0 0.85

SRC21-863 240833 1368650 150 115 -62 72 18.0 21.0 3.0 0.57

SRC21-864 No Significant results

SRC21-865 240832 1368688 148 102 -58 66 23.0 28.0 5.0 1.05

56.0 58.0 2.0 2.05