Note 5 - Mineral Properties - Costs Incurred for Exploration and Evaluation Activities (Details) - CAD ($)		12 Months Ended
		May 31, 2019	May 31, 2018
Exploration expenditures (notes 5 and 6)		$ 5,636,641	$ 5,333,180
North Bullfrog [Member]
Exploration expenditures (notes 5 and 6)	[1]	889,146	1,007,097
Mother Lode Property [Member]
Exploration expenditures (notes 5 and 6)	[2]	4,747,495	4,326,083
Assay [Member]
Exploration expenditures (notes 5 and 6)		582,113	787,454	[1]
Assay [Member] | North Bullfrog [Member]
Exploration expenditures (notes 5 and 6)	[1]	14,839	44,703
Assay [Member] | Mother Lode Property [Member]
Exploration expenditures (notes 5 and 6)	[2]	567,274	742,751
Drilling [Member]
Exploration expenditures (notes 5 and 6)		1,996,854	1,882,239
Drilling [Member] | North Bullfrog [Member]
Exploration expenditures (notes 5 and 6)	[1]	208,421
Costs Recovered for Exploration and Evaluation Activities, Gross	[1]		(3,265)
Drilling [Member] | Mother Lode Property [Member]
Exploration expenditures (notes 5 and 6)	[2]	1,788,433	1,885,504
Equipment rental [Member]
Exploration expenditures (notes 5 and 6)		99,953	105,663
Equipment rental [Member] | North Bullfrog [Member]
Exploration expenditures (notes 5 and 6)	[1]	33,173	15,698
Equipment rental [Member] | Mother Lode Property [Member]
Exploration expenditures (notes 5 and 6)	[2]	66,780	89,965
Field Costs [Member]
Exploration expenditures (notes 5 and 6)		261,679	348,716
Field Costs [Member] | North Bullfrog [Member]
Exploration expenditures (notes 5 and 6)	[1]	13,620	33,310
Field Costs [Member] | Mother Lode Property [Member]
Exploration expenditures (notes 5 and 6)	[2]	248,059	315,406
Geological Geophysical [Member]
Exploration expenditures (notes 5 and 6)		734,396	739,346
Geological Geophysical [Member] | North Bullfrog [Member]
Exploration expenditures (notes 5 and 6)	[1]	83,972	80,771
Geological Geophysical [Member] | Mother Lode Property [Member]
Exploration expenditures (notes 5 and 6)	[2]	650,424	658,575
Land Maintenance and Tenure [Member]
Exploration expenditures (notes 5 and 6)		686,385	482,680
Land Maintenance and Tenure [Member] | North Bullfrog [Member]
Exploration expenditures (notes 5 and 6)	[1]	414,636	337,695
Land Maintenance and Tenure [Member] | Mother Lode Property [Member]
Exploration expenditures (notes 5 and 6)	[2]	271,749	144,985
Permits [Member]
Exploration expenditures (notes 5 and 6)		163,207	122,282
Permits [Member] | North Bullfrog [Member]
Exploration expenditures (notes 5 and 6)	[1]	7,546	9,036
Permits [Member] | Mother Lode Property [Member]
Exploration expenditures (notes 5 and 6)	[2]	155,661	113,246
Studies [Member]
Exploration expenditures (notes 5 and 6)		990,201	749,658
Studies [Member] | North Bullfrog [Member]
Exploration expenditures (notes 5 and 6)	[1]	98,904	478,904
Studies [Member] | Mother Lode Property [Member]
Exploration expenditures (notes 5 and 6)	[2]	891,297	270,754
Travel [Member]
Exploration expenditures (notes 5 and 6)		121,853	115,142
Travel [Member] | North Bullfrog [Member]
Exploration expenditures (notes 5 and 6)	[1]	14,035	10,245
Travel [Member] | Mother Lode Property [Member]
Exploration expenditures (notes 5 and 6)	[2]	$ 107,818	$ 104,897

[1] The Company's North Bullfrog project consists of certain leased patented lode mining claims and federal unpatented mining claims owned 100% by the Company.

[2] Pursuant to a purchase agreement made effective June 9, 2017 between Corvus Nevada and Goldcorp USA, Inc. ("Goldcorp USA"), Corvus Nevada has acquired 100% of the Mother Lode property (the "Mother Lode Property"). In addition, Corvus Nevada staked two additional adjacent claim blocks to the Mother Lode Property. In connection with the acquisition, the Company issued 1,000,000 common shares at a price of $0.81 per common share to Goldcorp USA (note 6). The Mother Lode Property is subject to an NSR in favour of Goldcorp USA. The NSR pays 1% from production at the Mother Lode Property when the price of gold is less than USD 1,400 per ounce and an additional 1% NSR for a total of 2% NSR when gold price is greater than or equal to USD 1,400 per ounce.