Note 14 - Segmented Information - Operating Results by Geographic Segments (Details) - USD ($)	3 Months Ended
	Oct. 31, 2019	Oct. 31, 2018
Mineral Property Expenditures	$ 1,523,451	$ 866,243
General and administrative	2,315,170	2,258,935
Depreciation, amortization and accretion	76,386	88,776
	3,915,007	3,213,954
Loss from operations	(3,915,007)	(3,213,954)
Other income (expenses)	(1,129,248)	(242,640)
Loss before income taxes	(5,044,255)	(3,456,594)
United States Texas [Member]
Mineral Property Expenditures	1,154,342	578,822
General and administrative	1,700,877	1,561,757
Depreciation, amortization and accretion	67,496	80,085
	2,922,715	2,220,664
Loss from operations	(2,922,715)	(2,220,664)
Other income (expenses)	(1,215,203)	(627,583)
Loss before income taxes	(4,137,918)	(2,848,247)
United States Arizona [Member]
Mineral Property Expenditures	24,572	30,121
General and administrative	3,389	3,389
Depreciation, amortization and accretion
	27,961	33,510
Loss from operations	(27,961)	(33,510)
Other income (expenses)	(4,767)	(4,767)
Loss before income taxes	(32,728)	(38,277)
United States Wyoming [Member]
Mineral Property Expenditures	148,043	147,876
General and administrative	34,713	31,370
Depreciation, amortization and accretion	3,717	3,719
	186,473	182,965
Loss from operations	(186,473)	(182,965)
Other income (expenses)		300
Loss before income taxes	(186,473)	(182,665)
United States Other States [Member]
Mineral Property Expenditures	20,111	23,875
General and administrative	652	261
Depreciation, amortization and accretion	249	249
	21,012	24,385
Loss from operations	(21,012)	(24,385)
Other income (expenses)
Loss before income taxes	(21,012)	(24,385)
CANADA
Mineral Property Expenditures		15,588
General and administrative	553,706	611,470
Depreciation, amortization and accretion	2,589	3,898
	556,295	630,956
Loss from operations	(556,295)	(630,956)
Other income (expenses)	89,181	387,869
Loss before income taxes	(467,114)	(243,087)
PARAGUAY
Mineral Property Expenditures	176,383	69,961
General and administrative	21,833	50,688
Depreciation, amortization and accretion	2,335	825
	200,551	121,474
Loss from operations	(200,551)	(121,474)
Other income (expenses)	1,541	1,541
Loss before income taxes	$ (199,010)	$ (119,933)