Prime Mining Files NI 43-101 Technical Report on the Los Reyes Project, Mexico

VANCOUVER, British Columbia, April 07, 2020 (GLOBE NEWSWIRE) -- Prime Mining Corp. (TSX.V:PRYM) (OTCQB: PRMNF) (Frankfurt:A2PRDW) (“Prime” or the “Company”) is pleased to announce that a technical report titled “Technical Report Los Reyes Property Sinaloa, Mexico” has been filed. The technical report was prepared by Stantec Consulting Ltd. (“Stantec”) for Prime’s Los Reyes Oxide Gold and Silver Project located near Cosalá, Mexico, and is in support of Prime Mining’s April 2, 2020 news release announcing its new mineral resource estimate, effective April 2, 2020.

The new mineral resource estimate increases total oxide mineralized material and upgrades the assurance category estimate reliability. The new pit constrained Updated Resource (at 0.22 g/t Au cutoff) increased to 19.8 million tonnes Measured and Indicated plus 7.1 million tonnes Inferred from 6.8 million tonnes Indicated and 3.2 million tonnes Inferred historic global resource (at 0.5 g/t Au cutoff).

The Updated Resource contains 833,082 gold equivalent (“AuEq”) ounces Measured and Indicated at 1.31 g/t and 261,132 AuEq ounces Inferred at 1.14 g/t.

The following is a summary of pit constrained AuEq ounces at various cutoffs:

Table 1: Summary of Pit Constrained Updated Resource in AuEq Ounces

Cutoff	Assurance Category	Tonnes	Average AuEq	Contained AuEq
			Grade (g/t)	Ounces
0.22 g/t cutoff Base Case	Measured & Indicated	19,752,000	1.31	833,082
	Inferred	7,094,000	1.14	261,132
0.50 g/t cutoff	Measured & Indicated	11,822,000	1.85	701,873
	Inferred	3,956,000	1.65	209,344
0.70 g/t cutoff	Measured & Indicated	8,697,000	2.21	618,123
	Inferred	2,603,000	2.09	175,232
0.90 g/t cutoff	Measured & Indicated	6,746,000	2.54	550,207
	Inferred	1,859,000	2.48	148,160
1.0 g/t cutoff	Measured & Indicated	5,914,000	2.72	516,251
	Inferred	1,685,000	2.59	140,530

Gold equivalent calculations are based on a gold to silver ratio of 1:83. Pit constrained mineral resources are reported at cut-off grades within conceptual pit shells. The total base case resulting pit strip ratio is 4.6:1 waste to mineralized material. Both gold and silver values are used to determine the value of a given block and the pit shell is defined by: a 0.22 g/t minimum gold cutoff grade, US$2.40 per tonne mining cost, a gold price of US$1,329 per troy ounce and a silver price of US$16 per troy ounce. Mineralization density is based on laboratory analyses on specific lithologies and a default mine rock density is based on 2.6 tonnes/m³ for all other areas. Modifying factors considered for the definition of mineralized zones into classified resources having reasonable prospects for eventual economic extraction are: metallurgical recovery factors of 72% for gold and 25% for silver that are typical for conventional heap leach operations, no allowance for dilution and mining losses in the calculation of the cutoff grade, combined leaching, site costs and overhead of approximately US$4.30 per tonne placed on the leach pad and no refining and royalty costs have been applied.