REVENUE - Schedule of detailed information about revenue (Details) - CAD ($)	12 Months Ended
May 31, 2020	May 31, 2019
Revenue [Line Items]
Endeavor stream	$ 3,520,828	$ 7,852,661
Total revenue	3,611,101	7,852,661
COSE royalty
Revenue [Line Items]
Royalty	61,716	0
Joaquin royalty
Revenue [Line Items]
Royalty	$ 28,557	$ 0

Expiry date 2020-01-01: The income arising in the course of an entity's ordinary activities. Income is increases in economic benefits during the accounting period in the form of inflows or enhancements of assets or decreases of liabilities that result in an increase in equity, other than those relating to contributions from equity participants. Effective 2020-01-01: The income arising in the course of an entity's ordinary activities. Income is increases in assets, or decreases in liabilities, that result in increases in equity, other than those relating to contributions from holders of equity claims.

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+ Details