Expansion drilling intersected 5.10 gpt AuEq¹ over 11.4 metres and 4.86 gpt AuEq over 13.3 metres

Prime Mining Corp. (TSX-V: PRYM) (OTCQX: PRMNF) (Frankfurt: 04V3) is reporting drill results from four holes at the Z-T Area, one of three main zones hosting the gold-silver mineral resource estimate announced May 2, 2023 at the Company’s Los Reyes Project located in Sinaloa State, Mexico. A 2023 Technical Report was filed on June 13, 2023 and can be found on the Company’s website at https://primeminingcorp.ca/ and on SEDAR at www.sedar.com, under the Company’s Issuer Profile.

Two of the new core holes drilled at Tahonitas, in the southeast end of the Z-T Area (see Figures 1, 2), are located 100 to 200 metres below the recently announced resource pit shell. This drilling follows Prime’s news release of May 24, 2023 (link here), confirming the ongoing expansion of potential gold-silver resources in addition to and not included in the Company’s MRE.

Z-T Drilling Highlights:

• 5.10 gpt AuEq (3.96 gpt Au and 88.0 gpt Ag) over 11.4 m etw in hole 23TA-67, located 200 m below the MRE resource pit, including:
  • 27.20 gpt AuEq (24.50 gpt Au and 209.0 gpt Ag) over 1.5 m etw.
• 4.86 gpt AuEq (3.80 gpt Au and 82.0 gpt Ag) over 13.3 m etw in hole 23TA-69, located 100 m below the MRE resource pit, including:
  • 9.30 gpt AuEq (8.15 gpt Au and 89.2 gpt Ag) over 3.7 m etw.

Together the mineralization in these drill holes further defines two high-grade mineralized shoots separated by 250 m. These intercepts open a significant area of exploration upside relative to the MRE pit shell for the Z-T Area. They suggest a potential merging of the western, shallow plunging mineralized shoot encountered by hole 23TA-67 and the eastern, steeply plunging mineralized shoot intercepted by 23TA-69 (see Figure 3).

Prime Mining Corp. Chief Executive Officer Daniel Kunz commented, “Today’s exciting results from Z-T are significant as they further demonstrate high-grade mineralization at depth, and open significant potential for mineralization in these currently untested gaps. These are among the highest grades and deepest intercepts we have encountered at Z-T to date. We have been very encouraged with the results post-resource drilling cutoff at the south end of the Z-T structure. As a result, we will continue to focus on this area of the orebody, both down dip and along strike.”

Drilling will be ongoing through the upcoming rainy season with four drill rigs focusing on:

1. extending the high-grade Z-T shoots that remain open at depth, as well as along strike north and south;
2. expanding the two other MRE resource areas, including the eastern extensions of the Guadalupe System and Echeguran Shaft area; and,
3. exploring the new generative targets.

Figures 3 to 5 provide a visual summary of the Z-T Area extension drill program incorporating today’s reported drill results. Hole 23TA-67 is at an elevation of 320 masl and mineralization remains open at depth. Prime has already completed over 28,000 m of its planned 60,000 m 2023 drill program and will continue to evaluate its drilling plans using its success-based approach.

Figure 1: Los Reyes drilling update

Figure 2: Z-T drilling update

Figure 3: Z-T long section

Figure 4: Z-T (Tahonitas area) cross section A-A’

Figure 5: Z-T (Tahonitas area) cross section B-B’

 Link 1 – PDF Figures

Link 2 – PDF Drill Hole Tables

Note 1: Gold equivalent grades are calculated based on an assumed gold price of $US 1700 per ounce and silver price of $22 per ounce, based on the formula AuEq grade (gpt) = Au grade + Ag grade x ($22 / $1,700). Metallurgical recoveries are not considered in the in-situ grade estimate but are estimated to be 93% and 83% for gold and silver, respectively, when processed in a mill, and 72% and 25% respectively when heap-leached.

QA/QC Protocols and Sampling Procedures

Drill core at the Los Reyes project is drilled in predominately HQ size (63.5 millimetre “mm”), reducing to NQ (47.6 mm) when required. Drill core samples are generally 1.50 m long along the core axis with allowance for shorter or longer intervals if required to suit geological constraints. After logging intervals are identified to be sampled, the core is cut and one half is submitted for assay. RC drilling returns rock chips and fines from a 133.35 mm diameter tricone bit. The returns are homogenized and split into 2 halves, with one half submitted for analysis and the other half stored.

Sample QA/QC measures include unmarked certified reference materials, blanks, and field duplicates as well as preparation duplicates are inserted into the sample sequence and make up approximately 8% of the samples submitted to the laboratory for each drill hole.

Samples are picked up from the Project by the laboratory personnel and transported to their facilities in Durango or Hermosillo Mexico, for sample preparation. Sample analysis is carried out by Bureau Veritas and ALS Labs, with fire assay, including over limits fire assay re-analysis, completed at their respective Hermosillo, Mexico laboratories and multi-element analysis completed in North Vancouver, Canada. Drill core sample preparation includes fine crushing of the sample to at least 70% passing less than 2 mm, sample splitting using a riffle splitter, and pulverizing a 250-gram split to at least 85% passing 75 microns.

Gold in diamond drill core is analyzed by fire assay and atomic absorption spectroscopy of a 30 g sample (code FA430 or Au-AA23). Multi-element chemistry is analyzed by 4-Acid digestion of a 0.25-gram sample split (code MA300 or ME-ICP61) with detection by inductively coupled plasma emission spectrometer for a full suite of elements.

Gold assay techniques FA430 and Au-AA23 have an upper detection limit of 10 ppm. Any sample that produces an over-limit gold value via the initial assay technique is sent for gravimetric finish via method FA-530 or Au-GRA21. Silver analyses by MA300 and ME-ICP61 have an upper limit of 200 ppm and 100 ppm, respectively. Samples with over-limit silver values are re-analyzed by fire assay with gravimetric finish FA530 or Au-GRA21.

Both Bureau Veritas and ALS Labs are ISO/IEC accredited assay laboratories.

Qualified Person

Scott Smith, P.Geo., Executive Vice President of Exploration, is a qualified person for the purposes of National Instrument 43-101 and has reviewed and approved the technical content in this news release.

Additional Notes

Metres is represented by “m”; “etw” is Estimated True Width and is based on drill hole geometry or comparisons with other on-section drill holes; “Au” refers to gold, and “Ag” refers to silver; “gpt” is grams per metric tonne; some figures may not sum due to rounding; Composite assay grades presented in summary tables are calculated using a Au grade minimum average of 0.20 gpt or 1.0 gpt as indicated in “Au Cut-off” column of Summary Tables. Maximum internal waste included in any reported composite interval is 3.00 m. The 1.00 gpt Au cut-off is used to define higher-grade “cores” within the lower-grade halo.

About the Los Reyes Gold and Silver Project

Los Reyes is a rapidly evolving high-grade, low sulphidation epithermal gold-silver project located in Sinaloa State, Mexico. Since acquiring Los Reyes in 2019, Prime has spent approximately US$30 million on direct exploration activities and has completed over 120,000 m of drilling. On May 2, 2023, Prime announced an updated multi-million-ounce high-grade open pit constrained resource (see below, and refer to Note 1 and the May 2, 2023 press release for more details).

May 2, 2023 Resource Statement

Drilling is on-going and suggests that the three known main deposit areas (Guadalupe, Central and Z-T) are larger than previously reported. Potential also exists for new discoveries where mineralized trends have been identified outside of the currently defined resource areas.

Historic operating results indicate that an estimated 1 million ounces of gold and 60 million ounces of silver were recovered from five separate operations at Los Reyes between 1770 and 1990. Prior to Prime’s acquisition, recent operators of Los Reyes had spent approximately US$20 million on exploration, engineering, and prefeasibility studies.

About Prime Mining

Prime is managed by an ideal mix of successful mining executives, strong capital markets personnel and experienced local operators all focused on unlocking the full potential of the Los Reyes Project. The company has a well-planned capital structure with a strong management team and insider ownership.