Significant accounting policies (Tables)

12 Months Ended

Dec. 31, 2020

Significant Accounting Policies [Abstract]

Disclosure of detailed information about estimated useful life or depreciation rate [Table Text Block]

•	Capital works in progress		- not depreciated
•	Mining properties		- unit-of- production
•	Mining asset		- unit-of- production
•	Plant and Equipment
	◦	Equipment	- straight-line over 1 to 20 years
	◦	Other plant assets	- straight-line over 1 to 20 years/unit-of-production
•	ROU Assets		- straight -line over 1 to 20 years