Mineral Resource Estimate

The Full Technical Report of the Mother Lode Project will be filed by early November 2018

Mother Lode, Measured, Indicated, and Inferred Mineral Resource Estimations constrained by Whittle TM pit at a gold price of USD $1,250 per ounce

Resource Category Mill-Sulfide
@ 0.63 g/t COG
ROM Heap Leach
@ 0.06 g/t COG
Total
Kt Au g/t Kozs Kt Au g/t Kozs Kt Au g/t Kozs
Measured 3,292 1.41 149 20,035 0.29 185 23,327 0.45 334
Indicated 9,934 1.83 583 20,123 0.37 242 30,057 0.85 825
Total M & I 13,226 1.72 733 40,158 0.33 427 53,383 0.68 1,159
Inferred 2,168 1.60 112 14,073 0.29 129 16,241 0.46 241
 

Sensitivity of Mother Lode, Measured, Indicated, and Inferred Mineralization Estimations constrained by Whittle TM pit at a gold price of USD $1,000 per ounce

Resource Category Mill-Sulfide
@ 0.78 g/t COG
ROM Heap Leach
@ 0.07 g/t COG
Total
Kt Au g/t Kozs Kt Au g/t Kozs Kt Au g/t Kozs
Measured 2,133 1.79 123 17,441 0.31 174 19,574 0.47 297
Indicated 8,650 1.96 545 14,702 0.45 213 23,352 1.01 758
Total M & I 10,783 1.93 668 32,143 0.37 387 42,926 0.76 1,054
Inferred 941 1.82 55 5,966 0.34 65 6,907 0.54 120
  • See Cautionary Note to US Investors below
  • The Mineral Resources above are effective as of September 18, 2018
  • Mineral Resources that are not Mineral Reserves do not have demonstrated economic viability
  • Silver resources have not been included in the initial Mother Lode estimate
  • There are no known legal, political, environmental, or other risks that could materially affect the potential development of the Mineral Resources

The Mineral Resource estimation is based on 267 drill holes with 8,296 gold composites. Geologic volumes were defined by geologic interpretations and used to define the estimation. The resource was characterized by a high-grade core surrounded by lower grade mineralization. The high-grade core was estimated using Inverse Distance Squared. The surrounding mineralized portion of the deposit was estimated with Ordinary Kriging. To estimate the reasonable prospects of eventual economic extraction, Resource Development Associates Inc. confined the resources to mining volumes defined by Whittle TM analysis using the input parameters defined in Table 3. There are no known legal, political or environmental risks that could materially affect the potential development of the Mineral Resources.

WhittleTM Input Parameters used for the MLP Mineral Resource Estimation (USD)

Parameter Unit MLP-Mill MLP-Heap Leach
Mining Cost total tonne $1.40 $1.40
Au Cut-Off g/t 0.63 0.06
ProcessingCost process tonne $19.50 $1.20
Au Recovery % 80.0 74.0
Ag Recovery % 0.0 0.0
Admin Cost process tonne $0.50 $0.50
Refining & Sales $/Au oz $5.00 $5.00
Au Selling Price oz $1,250 $1,250
Slope Angle Degrees 60 60
  • assumes heap leach processing of disseminated oxidized  mineralization
  • assumes Pressure Oxidation  mill processing of MLP sulfide mineralization
  • Au Cut-Off - break-even grade derived from Whittle input parameters at USD $1,250 per ounce gold price

Assaying for the MLP holes has been performed American Assay Laboratories (“AAL”) in Sparks, Nevada.  Corvus has no business relationship with AAL beyond being a customer for analytical services.  The Sparks laboratory is Standards Council of Canada, Ottawa, Ontario Accredited Laboratory No. 536 and conforms with requirements of CAN-P-1579, CAN-P-4E (ISO/IEC 17025:2005).

Check assaying has been performed by Bureau Veritas North America (“BV”, formerly Inspectorate America Corporation), in Sparks Nevada and Vancouver, Canada, and ALS Minerals Laboratories (“ALS Minerals”), in Sparks, Nevada.  Corvus has no business relationship with BV or ALS Minerals beyond being a customer for analytical services.  The BV laboratory is Accredited Laboratory No. 720 and conforms to requirements of CAN-P-1579, CAN-P-4E (ISO 9001:2008) and ALS is Accredited Laboratory No. 660 and conforms to requirements of CAN-P-1579, CAN-P-4E (ISO/IEC 17025:2005).

Mr. Scott E. Wilson, CPG (10965), Registered Member of SME (4025107) and President of Resource Development Associates Inc., is an independent consulting geologist specializing in Mineral Reserve and Resource calculation reporting, mining project analysis and due diligence evaluations.  He is acting as the Qualified Person, as defined in NI 43-101, for the Mineral Resource estimate and has reviewed and approved the Mineral Resource estimate contained in this news release.  Mr. Wilson has over 29 years of experience in surface mining, resource estimation and strategic mine planning. Mr. Wilson and Resource Development Associates Inc. are independent of the Company under NI 43-101.

Mr. Wilson, a qualified person, has verified the data underlying the information disclosed herein, including sampling, analytical and test data underlying the information by reviewing the reports of AAL, methodologies, results and all procedures undertaken for quality assurance and quality control in a manner consistent with industry practice, and all matters were consistent and accurate according to his professional judgement.  There were no limitations on the verification process.