I-Minerals Produces its Best Ever Metakaolin

VANCOUVER, BC--(Marketwired - September 18, 2017) - I-Minerals lnc. (TSX VENTURE: IMA) (OTCQB: IMAHF) (FRANKFURT: 61M) (the "Company")announces that further to the Company's press release of August 29, 2017, it has received results of ASTM C618-15 testing from CTL Thomson in Denver, CO of the various metakaolin products produced using the flash calcination technologies of FLSmidth in Allentown, PA. The key test is the water requirement measured as a percentage of the control samples with 115% of control the acceptable maximum. Four samples representative of calcining temperatures of 700, 750, 800 and 850° C were sent for testing and all fell in the range of 108-110% of control and hence handily met the ASTM C618-15 water demand specifications.

"As part of the last several pilot plants, we have experimented with particle sizes and other inputs," stated Thomas Conway President and CEO of I-Minerals Inc. "However, this metakaolin, produced using the flash calcination technology, has created the best combination of strength, lowest water demand and color. As noted in our press release of August 29, initial testing of the use of hydrocyclones to make the clay/sand separation generated a cleaner cut resulting in higher clay recovery. Hence not only are we making the best metakaolin we ever have, but the hydrocyclone technology stands to increase metakaolin production with potential to modestly reduce both CAPEX and OPEX."

With respect to the 28-day Strength Activity Index (%) number, the minimum threshold to achieve to meet the ASTM C618-15 standard is 75. The four samples sent for testing resulted in values from 86.4-94.3 % and are expected to increase with additional time. For comparative purposes fly ash, the most common pozzolan, generally demonstrates strength numbers in the mid-80s, although there is variability across fly ash products.

"These results indicate we can make a pozzolan at least as good as high-quality fly ash," continued Conway. "With fly ash becoming scarcer as coal fired electric plants shift to gas or are shut down, a consistent supply of quality pozzolans is becoming increasingly challenging. Water demand is the test that inhibits the success of many natural pozzolans and meeting the specifications bodes very well for the market opportunities for our metakaolin in the Pacific Northwest. Having a high quality metakaolin alongside our best in class K-spar, our world class halloysite and the highest SiO₂, lowest iron quartz in the Pacific Northwest positions the Company very well as we push forward towards eventual production of these high-quality minerals."

A. Lamar Long, CPG, is a qualified person ("QP") for I-Minerals Inc. and has reviewed and approved the contents of this release

About I-Minerals Inc.

I-Minerals is developing multiple deposits of high purity, high value halloysite, quartz, potassium feldspar and kaolin at its strategically located Helmer-Bovill property in north central Idaho. A 2016 Feasibility Study on the Bovill Kaolin Deposit led by GBM Engineers LLC, who were responsible for overall project management and the process plant and infrastructure design, including OPEX and CAPEX calculated an After Tax NPV of US$249.8 million with a 25.8% After Tax IRR. Initial CAPEX was estimated at $108.3 million with a 3.7 year After Tax payback. Other engineering services were provided by HDR Engineering, Inc. (all environmental components; hydrology / hydrogeology; road design); Tetra Tech, Inc. (tailings storage facility design); Mine Development Associates (mine modelling; ore scheduling; mineral reserve estimation); and SRK Consulting (U.S.) Inc. (mineral resource estimation). The project has received mine and water permits from the State of Idaho.

I-Minerals Inc.

Per: "Thomas M. Conway"

Thomas M. Conway, President & CEO

This News Release includes certain "forward looking statements" within the meaning of the United States Private Securities Litigation Reform Act of 1995. Without limitation, statements regarding potential mineralization and resources, exploration results, and future plans and objectives of the Company are forward looking statements that involve various risks. Actual results could differ materially from those projected as a result of the following factors, among others: changes in the world-wide price of mineral market conditions, risks inherent in mineral exploration, risk associated with development, construction and mining operations, the uncertainty of future profitability and uncertainty of access to additional capital.

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