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STAR – Orion South Diamond Project Revised Mineral Resources Estimate Exhibits Significant Increase Total Indicated: 72 Million Carats, Total Inferred: 15 Million Carats

Resource Estimates

NEWS RELEASE July 24, 2024

Stock Symbol: DIAM: TSX Saskatoon, Saskatchewan

STAR – ORION SOUTH DIAMOND PROJECT

REVISED MINERAL RESOURCES ESTIMATE EXHIBITS SIGNIFICANT INCREASE

TOTAL INDICATED: 72 MILLION CARATS, TOTAL INFERRED: 15 MILLION CARATS

SASKATOON, Saskatchewan, July 24, 2024 – Star Diamond Corporation (“Star Diamond” or the “Company”)

is pleased to announce a significant increase in the estimated Mineral Resources for the Star - Orion South

Diamond Project (the “Project”).

Highlights

• Indicated Mineral Resources on Star have increased 22 percent to 34.8 million carats and the grade

has increased 20 percent to 19.4 cpht

• Indicated Mineral Resources on Orion South have increased 37 percent to 36.9 million carats and the

grade has increased 32 percent to 17.9 cpht

• Star Diamond has determined that no additional bulk sampling is required on the Orion South

Kimberlite for the rigorous estimation of these Mineral Resources, and this results in the savings of

millions of dollars in exploration expenditures and shaves significant time off the completion of the Pre-

Feasibility Study (“PFS”).

President & CEO, Ewan Mason said: "Our technical team and outside consultants have been working extremely

hard for the last year and a half to arrive at this incredible outcome. Not only has the requirement for a bulk

sample costing tens of millions of dollars been removed but we have reduced the time to complete a Feasibility

Study significantly. We intend to have a Feasibility Study completed by the end of 2026, with hopes that shovels

could be in the ground within 3 -5 years, subject to project financin g, permitting and updated environmental

approvals. Additionally, such a significant increase in grade and total carats across both pipes bodes well for

project economics. It is full speed ahead on the PFS".

Revised Mineral Resources Estimate

Table 1. Revised Mineral Resources Estimates for the Star and Orion South Kimberlites

Star Kimberlite

Revised Mineral Resources Estimate

Orion South Kimberlite

Revised Mineral Resources Estimate

Resource

Category

Kimberlite

Unit

Tonnes

x1,000

Grade

cpht

Carats

x1,000

Resource

Category

Kimberlite

Unit

Tonnes

x1,000

Grade

cpht

Carats

x1,000

Indicated MJF 21,822 6.6 1,437 Indicated EJF Outer 46,673 16.3 7,593

Indicated EJF Outer 47,659 16.9 8,045 Indicated EJF Inner 94,177 25.7 24,219

Indicated EJF Inner 84,090 24.0 20,168 Indicated Pense 65,746 7.8 5,125

Indicated Pense 13,960 18.1 2,525 Indicated TOTAL 206,596 17.9 36,937

Indicated Cantuar 12,060 21.7 2,622 Inferred EJF Outer 41,236 15.5 6,400

Indicated TOTAL 179,591 19.4 34,797 Inferred Pense 2,591 7.5 194

Inferred EJF Outer 34,100 14.4 4,923 Inferred P3 6,093 12.2 742

Inferred Pense 9,982 17.6 1,761 Inferred TOTAL 49,921 14.7 7,336

Inferred Cantuar 5,488 21.0 1,154

Inferred TOTAL 49,570 15.8 7,838

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Table Notes Apply to Table 1

1. Canadian Institute of Mining and Metallurgy (“CIM”) definitions were followed for classification of mineral

resources.

2. Star Kimberlite Units: Cantuar, Pense, Early Joli Fou (“EJF”), & Mid Joli Fou (“MJF”).

3. Orion South Kimberlite Units: P3, Pense & Early Joli Fou (EJF).

4. Mineral Resources are constrained within a Whittle optimized pit shell.

5. Mineral Resources, which are not Mineral Reserves do not have demonstrated economic viability. The estimation

of Mineral Resources may be materially affected by environmental, permitting, legal, title, taxation, socio -

political, marketing or other relevant issues.

6. There is no guarantee that all or any part of the Mineral Resources will be converted into a Mineral Reserves.

7. Grade values are rounded to the first decimal.

8. The effective date of the Revised Mineral Resources estimate is July 24, 2024.

9. The EJF Inner and Outer kimberlite units for both deposits are based on detailed kimberlite geology recorded from

the core logging of the pattern drilling program. The EJF Inner represents coarser grained EJF kimberlite that

occurs within the volcanic crater and the EJF Outer includes finer grained EJF kimberlite that lies on and outside

the crater rim. This Revised M ineral Resources estimate acknowledges that the transition from Inner to Outer is

geologically gradational.

Senior Vice President Corporate Development , George Read said: “Star Diamond is very pleased with the

substantial increase in grade and carats in the Indicated Resource category of this Revised Mineral Resource s

estimate, which has been rigorously prepared to diamond industry standards using meticulously reviewed

datasets. Revised diamond grade estimates are assigned to the Company’s established geological models for

the Star and Orion South diamond deposits using robust parameters consistent with previous studies. Rio Tinto

Exploration Canada’s (“RTEC”) successful development and execution of the Trench Cutter (“TC”) sampling

program and diamond recovery in the modern Consulmet Bulk Sample Plant, generated a diamond parcel that

can be integrated with diamond parcels from previous underground bulk samplin g and LDD programs. The TC

diamond parcel has improved the overall diamond grade and Size Frequency Distribution (“SFD”) used by Star

Diamond to estimate the revised Mineral Resources of both Star and Orion South. The consequent reduction in

the average diamond price due to the addition of smaller stones from enhanced recovery, is significantly offset

by the larger grade increase. We are also pleased to have diamond expert Mr. Peter Ravenscroft supervise this

Mineral Resources update after the completion of RTEC’s ten hole TC Program at the Star Kimberlite in 2019,

as he not only brings over 40 years of diamond resource estimation expertise with some of the major diamond

companies in the world, but also clearly aligns our Star - Orion South Diamond Project Mineral Resource s

estimate with established diamond industry standards. Estimation of th ese Revised Mineral Resource s has

taken a more pragmatic approach with careful consideration of the geological controls on diamond distribution.

Particular attention has been given to variations in diamond SFD, in addition to diamond grade. This approach

has resulted in a substantial increase in the Indicated Resources for both Star and Orion South. The Star – Orion

South Diamond Project now has one of the largest undeveloped Indicated Resources found in any diamond

project in the world . The diamond populations of the EJF and Cantuar kimberlite units at Star and the EJF

kimberlite unit at Orion South have significantly coarse diamond SFD, from which we can anticipate the recovery

of large, high quality (Type IIa) diamonds in future production.”

The scientific and technical information contained in this press release has been prepared and verified by A.C.A.

Howe International Limited (“Howe”), under the supervision of Mr. Daniel C. Leroux, M.Sc., P. Geo. and the

Mineral Resource estimation methodology under the supervision of Peter Ravenscroft, FAusIMM, of

Ravenscroft Mining Advisors, an independent mining consultant, and a Qualified Person (“QP”) within the

meaning of National Instrument 43 -101 – Standards of Disclosure for Mineral Projects ( “NI 43-101”) of the

Canadian Securities Administrators. This Revised Mineral Resources estimate uses diamond industry standard

methods which are rigorously applied to the Star and Orion South evaluation data, acknowledging the

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significant control that fundamental kimberlite geology has on the distribution of diamonds within these

deposits. The goal of the Revised Mineral Resources estimate was to incorporate additional detailed diamond

stone size frequency information obtained by RTEC into the dataset previous ly used in the 2015 Mineral

Resource Estimate, with particular interest in the smaller (+1, +3 & +5 DTC), but valuable stones, which were

inefficiently recovered in past exploration programs. A dvances in processing flow sheets and updated

processing technology have enabled the efficient recovery of these small diamonds by modern processing

plants. The grade alignment process used by Mr. Ravenscroft in 2015 has been updated with the Star TC

diamond data and subsequently applied to the Orion South Kimberlite.

Mineral Resources Estimation Methodology

Revised grade estimates at Star and Orion South have been based on a diamond industry standard approach

using alignment of sample diamond size frequency distributions. Peter Ravenscroft explains: “This approach

has allowed for the development of unbiased grade estimates that take into account the effects of using

necessarily small samples in a diamond deposit with relatively low grade but coarse stone size. At Orion South,

it has also provided a means of resolving sampling results from several sampling campaigns with different

drilling methodologies and different sample plant flowsheets. Final alignment with underground bulk sample

results and block model interpolation with appropriate smoothing has resulted in robust estimates of grade at

a required level of detail for feasibility study of the Star and Orion South deposits."

Economic Assumptions

CIM standards and Securities Commission disclosure regulations require that a Mineral Resource can only be

declared on a mineral deposit which has “reasonable prospects for eventual economic extraction”. The

reported Mineral Resource for Star and Orion Sou th are constrained using a Whittle pit optimization. The

Mineral Resources reported in Table 1 comprise the kimberlite that is constrained within the optimized Whittle

pit shell . Diamond values for this resource statement are based on the June 20 24 High mo deled prices

determined by in-house Diamond Specialist, Nelson Karun . This Revised Mineral Resource s estimate includes

only stones recovered larger than +1 DTC diamond sieve and considers all kimberlite above 90 metres above

mean sea level or to a depth of 360 metres below surface in Star and 375 metres below surface in Orion South,

with the surface being defined by the Digital Terrain Model.

Decision on Orion South Bulk Sampling

Star Diamond , working i n close consultation with Peter Ravenscroft, has determined that only limited

improvements in precision could be achieved by additional, prohibitively costly bulk sample programs, and that

the extensive work already completed will allow for robust diamond price estimates on both Star and Orion

South, with associated confidence limits allowing for quantified risk analysis as part of the PFS. This conclusion

has been reached based on the following:

• Comprehensive sorting and valuation of all stones recovered from LDD and Underground sampling

campaigns over the last 20 years, allowing for the combination of sample diamonds into significantly

larger parcels.

• Detailed comparison of quality distributions between Orion South and Star, identifying some clear

differences as well as some strong similarities, as would be expected from closely located kimberlites

in the same cluster.

• Analysis of the relative precision of price estimates from samples of a different size, specifically where

prices are influenced by large and high value stones as at Star and Orion South.

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Qualified Persons

Peter John Ravenscroft, FAusIMM, is the owner of Ravenscroft Mining Advisors based in Australia. He has a

Bachelor of Science degree in Mathematical Statistics from the University of Cape Town in 1979, and the

equivalent of a Masters degree in Geostatistics from the Ecole des Mines de Paris in 1985. Peter has practised

his profession for 45 years and has been directly involved in resource and reserve estimation, mine planning

and project evaluation for a wide range of commodities. This includes more than ten diamond properties in

Africa, Australia and Canada while working 7 years for De Beers and 17 years in technical and executive roles

for Rio Tinto, where at one point he was Competent Person for all diamond operations in the company. As a

result of his experience and qualifications, he is a QP as defined in NI 43–101.

Daniel C. Leroux, M.Sc., P.Geo. is a Senior Associate Geologist of Howe’s UK office. He is a member of the

Association of Professional Geoscientists of Ontario (“APGO”) and the Association of Professional Engineers and

Geoscientists of Saskatchewan (“APEGS”). He graduated from Laurentian University with both a Bachelor of

Science degree in Geology (1993) and a Master of Science in Mineral Exploration (2013), respectively. Mr.

Leroux has practised his profession for over 30 years, of which he has a total of 2 5 years of direct experience

with diamond projects located in Canada, Africa, Rus sia and South America, including managerial

responsibilities for all various exploration stage diamond projects from conceptual grassroots exploration

projects to bulk sampling, diamond resource estimation and pre -feasibility to feasibility studies on advanced

diamond projects. As a result of his experience and qualifications, he is a QP as defined in NI 43–101.

Next Steps

Star Diamond will file a Technical Report in respect of the Revised Mineral Resources estimate as soon as it is

available, and in any event within the regulated 45 -day period after this news release. The Revised Mineral

Resources estimate will now be incorporated into a re-optimized open pit mine plan for the Project, which will

include a re-evaluation of Mineral Reserves and an economic assessment based thereon. It is anticipated this

work will be completed during 2024-25 and will result in a revised PFS including a revised statement of Mineral

Reserves for the Project, if warranted, and an economic assessment based thereon. Accordingly, the mineral

resources and economic assessment previously disclosed by Star Diamond for the Project should no longer be

relied upon.

The Project

The Project is located in central Saskatchewan some 60 kilometres east of the city of Prince Albert. The Project

is in close proximity to established infrastructure, including paved highways and the electrical power grid, which

provide significant advantages for future mine development.

All technical information in this press release has been prepared under the supervision of George Read, Senior

Vice President Corporate Development, a registered Professional Geoscientist in the Provinces of

Saskatchewan and British Columbia and Mark Shime ll, Vice President Exploration, a registered Professional

Geoscientist in the Provinces of Saskatchewan and Alberta, who are Star Diamond’s QP’s under the definition

of NI 43-101.

About Star Diamond Corporation

Star Diamond is a Canadian -based corporation engaged in the acquisition, exploration and development of

mineral properties. Shares of Star Diamond trade on the Toronto Stock Exchange under the trading symbol

“DIAM”. Star Diamond’s most significant asset is its 100% interest in the Fort à la Corne Project in central

Saskatchewan. These kimberlites are located in close proximity to established infrastructure, including paved

highways and the electrical power grid, which provide significant advantages for future mine development.

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For further information, please contact:

Phone: (306) 664-2202

Email: [email protected]

Website www.stardiamondcorp.com

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YouTube - https://youtube.com/@StarDiamondCorp

Caution Regarding Forward-looking Statements

This press release contains "forward -looking statements" and/or "forward -looking information" (collectively, "forward -looking

statements") within the meaning of applicable securities legislation. All statements, other than statements of historical fact, are forward-

looking statements. Forward-looking information is often, but not always, identified by the use of words such as "anticipate", "believe",

"expect", "plan", "intend", "forecast", "target", "project", "guidance", "may", "will", "should", "could", "estimate", "predict" or similar

words suggesting future outcomes or language suggesting an outlook. In particular, statements regarding S tar Diamond 's future

operations, future exploration and development activities or other development plans constitute forward- looking statements. By their

nature, statements referring to mineral reserves or mineral resources constitute forward-looking statements.

Forward-looking statements in this press release include, but are not limited to statements with respect to the Revised Mineral

Resources Estimate; pricing information and other assumptions and parameters; improvement in the Mineral Resource estimate;

statements regarding the processing and analysis of, and reporting of results from, the TC bulk samples previously collected by RTEC;

the re-optimization of the Star and Orion South open pits; the potential proportion of Type IIa diamonds in the Star and Orion South

kimberlites and the potential for recovery of large high quality diamonds; the publication of the Technical Report; and the aim of the

Company to undertake a PFS and Feasibility Study and timelines.

These forward -looking statements are based on Star Diamond's current beliefs as well as assumptions made by and information

currently available to Star Diamond and involve inherent risks and uncertainties, both general and specific. Risks exist that forward-

looking statements will not be achieved due to a number of factors including, but not limited to, developments in world diamo nd

markets, changes in diamond prices, risks relating to fluctuations in the Canadian dollar and other currencies relative to the US dollar,

changes in exploration, development or mining plans due to exploration results and changing budget priorities of Star Diamond, the

impact of changes in the laws and regulations regulating mining exploration, development, closure, judicial or regulatory judgments and

legal proceedings, operational and infrastructure risks and the additional risks described in Star Diamond's most recently fi led Annual

Information Form, annual and interim MDA.

For further information: [email protected] or (306) 664-2202

www.stardiamondcorp.com

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