FRONTIER LITHIUM ANNOUNCES EXPANSION OF SPARK DEPOSIT - 18.8 Mt IN INDICATED AND 29.7 Mt IN INFERRED CATEGORIES

SUDBURY, Feb. 28, 2023 - Frontier Lithium Inc. (TSXV: FL) (FRA: HL2) (OTCQX: LITOF) (the "Company" or "Frontier") is pleased to report an updated mineral resource estimate (MRE) for the Spark deposit, the second delineated premium spodumene-bearing lithium deposit at the PAK Lithium Project "Project". The resource estimation has been prepared by BBA E&C Inc. Table 1 is a summary of the mineral resource estimate.

Resource estimate update for Spark deposit includes:

• 18.8 million tonnes averaging 1.52% Li₂O in the Indicated category, a 30% increase in size;
• 29.7 million tonnes averaging 1.34% Li₂O in the Inferred category, a 64% increase in size;
• The Spark lithium deposit remains open along strike and at depth.

"We are very pleased to announce a substantive increase of the size of the Spark deposit following over 16,000m of drilling and channeling completed in 2022. Particularly encouraging is the increased lithium grade from 1.40 to 1.52% Li2O of the indicated category of the Mineral Resource Estimate. Overall, this equates to a 27% increase in the size of the combined lithium pegmatites at the PAK Lithium Project. The grade increase together with the previously released results further support the ensuing PFS.", commented Garth Drever, Vice President Exploration of Frontier Lithium.

Mineral Resource Estimate Notes

1. Mineral Resources were prepared in accordance with NI 43-101 and the CIM Definition Standards (2014). Mineral resources that are not mineral reserves do not have demonstrated economic viability. This estimate of mineral resources may be materially affected by environmental, permitting, legal, title, taxation, sociopolitical, marketing, or other relevant issues.
2. Open pit Mineral Resources are reported at a cut-off grade of 0.65 % Li2O that is based on a 6.0% spodumene concentrate prices of US$1,500/tonne and an exchange rate of 1.29.
3. Appropriate mining costs, processing costs, metal recoveries, and inter ramp pit slope angles were used by BBA to generate the pit shell.
4. Rounding may result in apparent summation differences between tonnes, grade, and contained metal content.
5. Tonnage and grade measurements are in metric units.
6. A bulk density factor of 2.74 was applied to the pegmatite and 2.70 was applied to the aplite.

Modeling was performed using Datamine Studio RM software with grades estimated using ordinary kriging (OK) interpolation methodology. Samples were composited at 2.0 metres down hole. Assessment of composites indicated no capping was required on the Li₂O grades. Block grades were estimated on a multi pass basis with a minimum and maximum number of composites and maximum number of composites per drillhole required for each estimation pass. Block size is 5 metres by 5 metres (y) by 5 metres (z).

Additional information about the Mineral Resource modeling methodology will be documented in the NI 43-101 technical report (the "Technical Report") to be issued within 45 days.

The Spark pegmatite, discovered in September 2018 and delineated in 2019 and 2021 with four drill programs (20 holes totaling 5,768.7m and 14 channels totaling 342.4m). During 2022 two more drill programs totaling 50 holes (15,983.6m) and 60m of channel sampling with objectives of upgrading Inferred mineral resource category to Indicated mineral resource were completed. The results from all channels and drilling have been previously reported. Figure 1 is a location map showing the project area.

Geological logging of channels and drill core combined with multi-element geochemistry indicates a high degree of compositional homogeneity throughout the deposit. The pegmatite consists primarily of spodumene-bearing sodic aplite which is typically fine to medium grained, light grey to greenish grey locally with coarser zonations consisting of megacrystic feldspar, fine to coarse-grained light grey to white spodumene, grey quartz and variable amounts of muscovite. The coarser grained zones are similar in appearance and composition to the LIZ (Lower Intermediate Zone) at the PAK deposit 2.3 km to the southwest.

Figure 2 is a plan-view compilation map showing the surface exposure and trace of the drill holes and channels completed at the Spark pegmatite.

Figure 3 is a 3D rendering of the pegmatite solid and pit shell of the Spark pegmatite. The deposit's current dimensions are roughly 500m in length by up to 250m in width. Drilling has extended the mineralized pegmatite to a depth of approximately 400m. It remains open in all directions.

All scientific and technical information in this release has been reviewed and approved by Todd McCracken, P.Geo., Director - Mining & Geology - Central Canada, BBA E&C Inc., the qualified person (QP) and Garth Drever, P.Geo., VP Exploration for Frontier Lithium Inc. the qualified person (QP) under the definitions established by National Instrument 43-101. Under Frontier's QA/QC procedures, all drilling was completed by Chenier Drilling Ltd. of Val Caron, ON using thin-walled BTW drill rods (4.2 cm core diameter) and a Reflex ACT III oriented core system. Using the Reflex system, the drill core was oriented and marked as it was retrieved at the drill. The core was boxed and delivered to the Frontier core shack where it was examined, geologically logged and marked for sampling. The core was photographed prior to sampling. Using a rock saw, the marked sample intervals were halved with one halve bagged for analysis. Sample blanks along with lithium, rubidium and cesium certified reference material was routinely inserted into the sample stream in accordance with industry recommended practices. Field duplicate samples were also taken in accordance with industry recommended practices. The samples were placed in poly sample bags and transported to Red Lake by Frontier employees and then shipped to AGAT Laboratories Ltd. (AGAT) in Mississauga, ON for quantitative multi-element analysis. AGAT is an ISO accredited laboratory. The core is stored on site at the Pakeagama Lake exploration camp.

Frontier Lithium is a preproduction business with an objective to become a strategic domestic supplier of spodumene concentrates for industrial users as well as battery-grade lithium hydroxide and other chemicals to the growing electric vehicle and energy storage markets in North America. The Company maintains the largest land position and resource in a premium lithium mineral district located in Ontario's Great Lakes region.

The PAK lithium project contains one of North America's highest-grade lithium resources. The project encompasses close to 27,000 hectares and remains largely unexplored; however, since 2013, the company has delineated two premium spodumene-bearing lithium deposits (PAK and Spark), located 2.3 kilometres apart. Exploration is continuing on the project through two other spodumene-bearing discoveries: the Bolt pegmatite (located between the PAK and Spark deposits), as well as the Pennock pegmatite (25 kilometres northwest of PAK deposit within the project claims). A 2021 preliminary economic assessment (National Instrument 43-101 technical report titled "NI 43-101 Technical Report, Pak Property, PAK, Red Lake Mining District, Ontario, Canada" by BBA E&C Inc., with an effective date of April 5, 2021) delivered a fully integrated lithium operation, including the mine and mill and the conversion plant for production of battery-quality lithium salts.

Neither the TSX Venture Exchange nor its Regulation Services Provider (as that term is defined in the policies of the TSX Venture Exchange) accepts responsibility for the adequacy or accuracy of this release. This release includes certain statements that may be deemed "forward-looking statements". All statements in this release, other than statements of historical facts, that address future production, reserve potential, exploration drilling, exploitation activities and events or developments that the Company expects are forward-looking statements. Although the Company believes the expectations expressed in such forward-looking statements are based on reasonable assumptions, such statements are not guarantees of future performance and actual results or developments may differ materially from those in the forward-looking statements. Factors that could cause actual results to differ materially from those in forward looking statements include market prices, exploitation and exploration successes, continued availability of capital and financing, and general economic, market or business conditions. Investors are cautioned that any such statements are not guarantees of future performance and those actual results or developments may differ materially from those projected in the forward-looking statements. For more information on the Company, Investors should review the Company's registered filings available at sedar.com.

SOURCE Frontier Lithium Inc.