Mining Interest, Plant and Equipment (Tables)

12 Months Ended

Apr. 30, 2019

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Summary of Mining Interest, Plant and Equipment

	Mining Interest			Plant and Equipment Mining			Plant and Equipment Altiplano			Corporate Office Equipment			Total
Cost
Balance, April 30, 2017	$	73,048		$	23,699		$	7,005		$	677		$	104,429
Additions		902			2,720			78			15			3,715
Impairment on equipment		(5,000	)		(1,925	)		—			—			(6,925	)
Effect of foreign exchange		(4,592	)		(1,318	)		(429	)		—			(6,339	)
Balance, April 30, 2018		64,358			23,176			6,654			692			94,880
Additions		1,338			1,055			92			25			2,510
Write down of equipment		0			0			(5,576	)		(2	)		(5,578	)
Effect of foreign exchange		2,734			1,238			876			0			4,848
Balance, April 30, 2019	$	68,430		$	25,469		$	2,046		$	715		$	96,660
Depreciation
Balance, April 30, 2017	$	39,657		$	11,190		$	228		$	433		$	51,508
Depreciation for the year		2,887			1,621			434			90			5,032
Impairment on equipment		—			(212	)		—			—			(212	)
Effect of foreign exchange		(2,232	)		(680	)		(12	)		—			(2,924	)
Balance, April 30, 2018		40,312			11,919			650			523			53,404
Depreciation for the year		1,923			1,768			118			90			3,899
Write down of equipment		0			0			(774	)		0			(774	)
Effect of foreign exchange		1,701			806			6			0			2,513
Balance, April 30, 2019	$	43,936		$	14,493		$	0		$	613		$	59,042
Carrying amounts
Balance, April 30, 2018	$	24,046		$	11,257		$	6,004		$	169		$	41,476
Balance, April 30, 2019	$	24,494		$	10,976		$	2,046		$	102		$	37,618