Alta Zinc : Gorno Scoping Study

ASX Announcement

24 November 2021

Cautionary Statement

The Scoping Study referred to in this ASX release has been undertaken for the purpose of initial evaluation of a potential development of the Gorno (Zn, Pb, Ag) Project in the Lombardy Region of Northern Italy. It is a preliminary technical and economic study of the potential viability of the Gorno Project. The Scoping Study outcomes, production target and forecast financial information referred to in this release are based on low accuracy level technical and economic assessments that are insufficient to support estimation of Ore Reserves. The Scoping Study has been completed to a level of accuracy of ±35% in line with a scoping level study accuracy. While each of the modifying factors was considered and applied, there is no certainty of eventual conversion to Ore Reserves or that the production target itself will be realised. Further exploration and evaluation work and appropriate studies are required before Alta Zinc (Alta) will be in a position to

uncertainties involved, investors should not make any investment decisions based solely on the results of theForScoping Study.

Of the Mineral Resources estimates scheduled for extraction in the Scoping Study production plan approximately 77% are classified as Indicated and 23% as Inferred during the 9-year production period evaluated. There is a low level of geological confidence associated with Inferred Mineral Resources and there is no certainty that further exploration work will result in the determination of Indicated Mineral Resources or that the production target itself will be realised. Inferred Mineral Resources comprise 22% of the production schedule in the first three years of operation and an average of 21% over the first five years of operation. Alta confirms that the financial viability of the Gorno Project is not dependent on the inclusion of Inferred Resources in the production schedule.

The Mineral Resources underpinning the production target in the Scoping Study have been prepared by a competent person in accordance with the requirements of the JORC Code (2012). The Competent Person's Statement is found in Appendix A of this ASX release. For full details of the Mineral Resources estimate, please refer to Alta ASX release dated 15 November 2021. Alta confirms that it is not aware of any new information

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or data that materially affects the information included in that release. All material assumptions and technical parameters underpinning the estimates in that ASX release continue to apply and have not materially changed.

This release contains a series of forward-looking statements. Generally, the words "expect," "potential", "intend," "estimate," "will" and similar expressions identify forward-looking statements. By their very nature forward-looking statements are subject to known and unknown risks and uncertainties that may cause ouronlyactual results, performance or achievements, to differ materially from those expressed or implied in any of our forward-looking statements, which are not guarantees of future performance. Statements in this release regarding Alta's business or proposed business, which are not historical facts, are forward-looking statements that involve risks and uncertainties, such as Mineral Resource estimates, market prices of metals, capital and operating costs, changes in project parameters as plans continue to be evaluated, continued availability of capital and financing and general economic, market or business conditions, and statements that describe Alta's future plans, objectives or goals, including words to the effect that Alta or management expects a stated condition or result to occur. Forward-looking statements are necessarily based on estimates and assumptions

usethat, while considered reasonable by Alta, are inherently subject to significant technical, business, economic, competitive, political and social uncertainties and contingencies. Since forward-looking statements address future events and conditions, by their very nature, they involve inherent risks and uncertainties. Actual results in each case could differ materially from those currently anticipated in such statements. Investors are cautioned not to place undue reliance on forward-looking statements, which speak only as of the date they are made.

Alta has concluded that it has a reasonable basis for providing these forward-looking statements and thepersonalforecast financial information included in this release. This includes a reasonable basis to expect that it will be able to fund the development of the Gorno Project upon successful delivery of key development

milestones and when required. The detailed reasons for these conclusions are outlined throughout this ASX release (including the Funding section of this announcement) and Section 1 in the Appendix. While Alta considers all of the material assumptions to be based on reasonable grounds, there is no certainty that they will prove to be correct or that the range of outcomes indicated by the Scoping Study will be achieved.

To achieve the range of outcomes indicated in the Scoping Study, pre-production funding estimated to be approximately US$114m may be required. There is no certainty that Alta will be able to source that amount of funding when required. It is also possible that such funding may only be available on terms that may be dilutive to or otherwise affect the value of Alta's shares. It is also possible that Alta could pursue other value realisation strategies such as a sale, partial sale or joint venture of the Gorno Project. This could materially reduce Alta's proportionate ownership of the Gorno Project.

No Ore Reserve has been declared. This ASX release has been prepared in compliance with the current JORC Code (2012) and the ASX Listing Rules. All material assumptions, including sufficient progression of all JORC modifying factors, on which the production target and forecast financial information are based have been

Forincluded in this ASX release.

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Alta Zinc Limited (ASX:AZI) (Alta or the Company) is pleased to announce the results of a Scoping Study (Study) for the Gorno Project (Gorno Project or the Project) Bergamo, Italy, which has been completed by CSA Global Consultants (CSA) with the assistance of a highly experienced and reputable specialist independent consultants.

The Study presents an initial evaluation of the financial viability of the Gorno Project and demonstrates strong production metrics and robust economics. It provides confirmation that the Gorno Project is commercially

o Sustaining capital estimated at US$42M (8% of operating cost)

• Positive financial metrics in the range of:

o Post Tax Net Present Value (NPV8) of approximately US$211M (A$288M) o Post-TaxInternal Rate of Return (IRR) of approximately 50%

o Payback period of approximately 3.5 years from final investment decision and approximately 2.5 years from first concentrate production

• Significant expansion and upside potential beyond Scoping Study

o Ongoing exploration drilling will run in conjunction with the DFS, targeting further resources definition and growth expected from the defined Exploration Target estimated as an additional 17.4Mt to 22Mt at grades ranging between 8.5 and 10.4% Zn, 1.9 and 2.4% Pb and 19 and 23g/t Ag from exploration to be undertaken in conjunction with next stage of study. Refer to ASX announcement 8 September 2021. The potential quantity and grade of the Exploration Target is conceptual in nature and therefore is an approximation. There has been insufficient

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exploration to estimate a Mineral Resource and it is uncertain if further exploration will result in the estimation of a Mineral Resource.

1. Ongoing metallurgical test-work and flowsheet design will target processing performance, equipment sizing, maximising metallurgical recoveries and optimising concentrate economics.

Of the Mineral Resources scheduled for extraction in the Scoping Study production plan approximately 77% are classified as Indicated and 23% as Inferred during the 9 year production period. There is a low level of geological onlyconfidence associated with Inferred Mineral Resources and there is no certainty that further exploration work will result in the determination of Indicated Mineral Resources or that the production target itself will be realised. Inferred Resources comprise 22% of the production schedule in the first three years of operation and an average of 21% over the first five years of operation. Alta confirms that the financial viability of the Gorno

Project is not dependent on the inclusion of Inferred Resources in the production schedule.

Geraint Harris, MD of Alta Zinc commented:

"This Scoping Study provides an initial evaluation of the Gorno Project that considered several possible options to define a project path to maximise project economics, minimise environmental and social impacts useand deliver maximum shareholder returns. In my opinion, Gorno is set to become a best-in-class modern underground mine with a minimal surface and environmental footprint. It will efficiently extract a high value mineralisation and convert it into one of the highest grade and cleanest zinc and lead concentrate products

available globally."

"The initial economic evaluations are compelling and provide substantial justification for the advancement of the asset, as well as highlighting areas where we can further grow the resource base and refine our strategy for progressing the asset throughout 2022."

personal"We take confidence from the study knowing that the robust NPV and IRR was based on a detailed analysis from highly experienced consultants, with commodity price assumptions significantly below current spot

levels. There are opportunities for further resource extension and optimisation, with the upside potential for increasing mine life and possibly throughput."

"The Company has achieved rapid resource growth and exploration success in the last 24 months notwithstanding challenges faced with Covid-19 both globally and within Italy and we remain committed to continuing an extensive program of exploration and development activities across our 100% owned Italian tenement package."

For

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Introduction

Alta is considering the potential to develop the Gorno Project in the Bergamo Region of Northern Italy, located approximately 28km from the rail hub of Bergamo and 230km from the Port of Genoa.

Existing infrastructure capable of servicing the Project includes:

• Two lane main highways directly to the mine and processing project sites;
• Established underground ramp access and surface infrastructure;
• Existing grid power, water, services and nearby population centres with available housing; and
• Airport, sea-ports and short transportation distances to European zinc and lead smelters

The Study confirmed that the Gorno Project is potentially a commercially viable development opportunity, with significant potential upside. A summary of the initial physical and financial evaluation of the Project at a 0.8Mtpa mine production rate is shown in Table 1 with additional details provided in the Study Executive Summary.

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