More Iamgold follow up on Monster.IAMGOLD FILES NI 43-101 TECHNICAL REPORT FOR PREVIOUSLY ANNOUNCED INITIAL MINERAL RESOURCE ESTIMATE FOR THE MONSTER LAKE PROJECT Toronto, Ontario, May 10, 2018 IAMGOLD Corporation (IAMGOLD or the Company) announced today that the Company has filed a National Instrument 43-101 (NI 43-101) Technical Report on the initial mineral resource estimate for the Monster Lake Project in Quebec, Canada, reported in the Companys news release dated March 28, 2018. The NI 43-101 was prepared by Charlotte Athurion, P.Geo., and Karine Brousseau, P.Eng., both of InnovExplo, under the supervision of Alain Carrier P.Geo., of InnovExplo. All are considered Qualified Persons as defined by NI 43-101. The NI 43-101 Technical Report may be found on the Company's website at www.iamgold.com or under the Company's profile at www.sedar.com and www.sec.gov/edgar.shtml. About IAMGOLD IAMGOLD (www.iamgold.com) is a mid-tier mining company with four operating gold mines on three continents. A solid base of strategic assets in North and South America and West Africa is complemented by development and exploration projects and continued assessment of accretive acquisition opportunities. IAMGOLD is in a strong financial position with extensive management and operational expertise. For further information please contact: Ken Chernin, VP Investor Relations, IAMGOLD Corporation Tel: (416) 360-4743 Mobile: (416) 388-6883 Laura Young, Director Investor Relations, IAMGOLD Corporation Tel: (416) 933-4952 Mobile: (416) 670-3815 Martin Dumont, Senior Analyst Investor Relations, IAMGOLD Corporation Tel: (416) 933-5783 Mobile: (647) 967-9942 Toll-free: 1-888-464-9999 info@iamgold.com Please note: This entire news release may be accessed via fax, e-mail, IAMGOLD's website