Note 6 - Restricted Cash - Restricted Cash (Details) - USD ($)	9 Months Ended	12 Months Ended
	Apr. 30, 2019	Jul. 31, 2018
Restricted cash, beginning of period	$ 1,789,899	$ 1,706,028
Reclamation deposit received from asset acquisition		73,973
Refund of reclamation deposit		(819)
Interest received	22,944	10,717
Restricted cash, end of period	$ 1,812,843	$ 1,789,899