Silvercorp Issues Updated Technical Report for the GC Mine

ANCOUVER, British Columbia – August 27, 2024 – Silvercorp Metals Inc. (“Silvercorp” or the “Company”) (TSX / NYSE American: SVM) is pleased to report the results of an updated Technical Report, prepared in accordance with National Instrument 43-101 Standards of Disclosure for Mineral Projects(“NI 43-101”) on Mineral Resources and Mineral Reserves for the Gaocheng Mine dated effective June 30, 2024 (“The GC 2024 Technical Report”), prepared by SRK Consulting China Ltd (“SRK”). The Gaocheng underground mine (“GC Mine”) is located in Guangdong Province, China.

Summary of the GC 2024 Technical Report

• Estimated Measured and Indicated Mineral Resources of 11.5 million tonnes (t) (inclusive of Mineral Reserves) grading 84 grams per tonne (g/t) silver (Ag), 1.18% lead (Pb), and 2.85% zinc (Zn), containing 31 million ounces (oz) silver, 136 thousand tonnes lead, and 327 thousand tonnes zinc.
  • In comparison with the 2021 Technical Report (Mineral Resources as of December 31, 2020), Measured and Indicated Resource tonnes have increased by 15%, and contained metal has increased by 18% for silver, 13% for lead and 16% for zinc.
• Estimated Proven and Probable Mineral Reserves of 5.0 million tonnes grading 81 g/t silver, 1.21% lead, and 2.84% zinc, containing 13 million oz silver, 60 thousand tonnes lead, and 141 thousand tonnes zinc.
  • In comparison with the 2021 Technical Report (Minera Reserves as of December 31, 2020), there has been a 20% increase in total Proven and Probable Mineral Reserves. The changes in total contained metal for silver, lead, and zinc are +4%, -2%, and +6% respectively.
• In comparison with the 2021 Technical Report, Inferred Resource tonnes have increased by 13%, and contained metal has increased by 11% for silver, 33% for lead and 16% for zinc.
• Based on Proven and Probable Mineral Reserves only, an annual production rate increase is planned from the current level of around 326,000 tonnes per annum (tpa) in FY2025 to between approximately 362,000 and 363,000 tpa from FY2026 to FY2037, and then 359,000 tpa in final FY2038. Annual production of silver is projected to be approximately 0.8 million ounces. There is also the potential to extend the Life of Mine (“LOM”) beyond 2037 via further exploration and development, particularly in areas with identified Inferred Resources.
• Using the LOM production profile based on the June 30, 2024 Mineral Reserves, at an 8% discount rate, the projected post-tax NPVs is $63.1M, with post-tax NPVs attributable to Silvercorp of $62.5 M (99% interest).

Mineral Resources

The June 30, 2024 Mineral Resources were estimated using a block modelling approach in Micromine. All grade estimation was completed using inverse distance squared. Resource estimates were made for a total of 256 mineralized vein structures for the GC Mine.

The Mineral Resources are reported above cut-offs after applying a minimum practical extraction width of 0.4 m. Cut-off grades are based on in situ values in silver equivalent (AgEq) terms in grams per tonne (g/t) and incorporate mining, trucking and processing costs, with metallurgical recoveries and payable values provided by Silvercorp and reviewed by the Qualified Person (QP) for the Mineral Resource estimate. AgEq formulas are shown in the footnotes of the table below.

The estimated Mineral Resources and metal content for the GC Mine as of June 30, 2024 are detailed in Table 1 below.

Table 1. GC Mine Mineral Resources and metal content for silver, lead, and zinc as of June 30, 2024

(Inclusive of Mineral Reserves)

Notes:

• Mineral Resource Statement as of June 30, 2024.
• The cut-off grade estimates are based on the forecast prices 25 USD/oz silver, 2,600 USD/t lead, and 3,300 USD/t zinc.
• AgEq = Ag+44.83*Pb+40.02*Zn.
• Mineral Resource are reported at a cut-off grade of 120 g/t AgEq.
• The veins within the depth less than 5m below surface are not included in the Mineral Resource.
• The totals may not compute exactly due to rounding.
• The Mineral Resource estimates for the GC Mine were carried out by Silvercorp and reviewed and approved by independent Qualified Person, Mark Wanless, Sci,Nat, FGSSA of SRK Consulting (South Africa) Ltd., who takes responsibility for these estimates.

A comparison of Mineral Resource estimates between December 31, 2020 and June 30, 2024 for payable metals indicates the following:

• Measured and Indicated tonnes have increased by 15% overall. The Inferred tonnes have increased by 13%.
• Measured and Indicated grades have increased for silver and zinc by 2% both. Measured and Indicated grade has decreased for lead by 2%.
• Inferred grades increased for lead and zinc by 23% and 2% respectively. Inferred grade has decreased for silver by 2%.
• The net result in the Measured and Indicated categories has been an increase in the contained silver, lead and zinc of 18%, 13% and 16% respectively.
• The net result in the Inferred category has been an increase in the contained silver, lead and zinc of 11%, 33%, and 16% respectively.

Reasons for the differences in grade, tonnes, and contained metal include updated interpretation of the mineralization, conversion to higher categories arising from drilling and level development, application of different cut-off grades (COGs), and depletion due to mining.

Mineral Reserves

The Mineral Reserve estimation is based on the assumption that current stoping practices will continue to be predominant at the GC Mine, namely cut and fill resuing and shrinkage stoping, using hand-held drills and hand-mucking or wheelbarrow within stopes, and loading to mine cars or truck by rocker-shovel or by load-haul-dump machine (LHD). The largely sub-vertical veins, generally competent ground, reasonably regular vein width, and hand-mining techniques using short rounds, allows a significant degree of selectivity and control in the stoping process. Minimum mining widths of 0.5 m for resuing and 1.0 m for shrinkage are assumed. The QP for the Mineral Reserve estimate has observed the mining methods at the GC Mine and considers the minimum extraction and mining width assumptions to be reasonable. Minimum dilution assumptions are 0.10 m of total overbreak for a resuing cut and 0.2 m of total overbreak for a shrinkage stope.

Mining dilution and recovery factors vary somewhat from stope to stope and with mining method. Average dilution factors have been estimated as 17% for resuing and 25% for shrinkage, while assumed mining recovery factors are 95% for resuing stopes and 92% for shrinkage stopes.

For the total tonnage estimated as GC Mine Reserves and included in the life of mine plan, approximately 33% is associated with resuing-type methods and approximately 67% with shrinkage.

The estimated Mineral Reserves and metal content for the GC Mine as of June 30, 2024 are detailed in Table 2 below.

Table 2. GC Mine Mineral Reserve estimates and metal content at June 30, 2024

Notes:

• Mineral Resource Statement as of June 30, 2024.
• The cut-off grade estimates are based on the forecast prices 22 USD/oz silver, 2,050 USD/t lead, and 2,650 USD/t zinc.
• AgEq = Ag+44.83*Pb+40.02*Zn.
• 150 g/t AgEq and 200 g/t AgEq COG was applied to shrinkage and resuing type stopes, respectively.
• The Mineral Reserves are reported on a metric dry tonne basis.
• The Mineral Reserves are reported at the reference point of ROM stockpile before crushing or directly crushing.
• The totals may not compute exactly due to rounding.
• The Mineral Reserve estimates for the GC Mine were carried out by Silvercorp and reviewed and approved by independent Qualified Person, Falong Hu, FAusIMM of SRK Consulting (China) Ltd., who takes responsibility for these estimates.

Total GC Mine Mineral Reserve tonnes are approximately 44% of Mineral Resource (Measured plus Indicated) tonnes. Silver, lead, and zinc Mineral Reserve grades are 96%, 103%, and 100% respectively of the corresponding Measured plus Indicated Mineral Resource grades. Metal conversion percentages for silver, lead, and zinc are 42%, 44%, and 43% respectively.

Some significant aspects of a comparison of Mineral Reserve estimates between December 31, 2020 (drilling cut off date of the previous Technical Report [1]) and June 30, 2024 (the GC 2024 Technical Report) are the following:

• 20% increase in total (Proven + Probable) GC Mine Mineral Reserve tonnes.
• Decrease in total GC Mineral Reserve silver, lead and zinc grades of 14%, 18% and 11% respectively.
• Increase in total GC Mineral Reserve metal content for silver and zinc of 4% and 6% respectively and decrease in lead metal of 2%.

[1] NI 43-101 Technical Report Update on the Gaocheng Ag-Zn-Pb Project in Guangdong Province, People’s Republic of China, Report Date October 6, 2021

The projected production profile for the GC Mine using current Mineral Reserves is shown in Table 3.

Table 3. GC Mine LOM production profile

Notes:

1.GC LOM average recoveries: Ag – 82.53%, Pb – 89.86%, Zn - 89.85%.

2. FY2025 Production shown is only for the three final quarters of financial year (July 2024 through to March 2025).
3. 3. Numbers may not compute exactly due to rounding.

The GC Mine continues to be a strongly viable operation based on current Mineral Reserves, with potential to extend its Mineral Resources via further exploration and development, particularly in areas with identified Inferred material.

Qualified Persons

All lead authors of the GC Technical Report qualify as independent Qualified Persons (“QPs”). Four of the independent authors have visited the GC Mine from April 23 to April 26, 2024. The QPs have examined all aspects of the project, including drill core, underground workings, processing plant and surface infrastructure. Assay data supporting the Mineral Resource estimate was verified by a QP by comparing a subset of assay results stored within the Mineral Resource database against assay certificates issued by the relevant reporting laboratory. The GC 2024 Technical Report will be made available for review on www.sedarplus.ca and on the Company’s website at www.silvercorpmetals.com within 45 days of this news release.

Mark Wanless, Pr.Sci, Nat, FGSSA of SRK Consulting (South Africa) Ltd.; Falong Hu, FAusIMM of SRK Consulting (China) Ltd.; and Guoliang Ma, P.Geo. of Silvercorp Metals Inc. are Qualified Persons as defined by NI 43-101. The Qualified Persons have reviewed and consented to this press release and believe it fairly and accurately represents the information in the Technical Report that supports the disclosure.