Note 6 - Mineral Rights and Properties - Mineral Property Expenditures (Details) - USD ($) $ in Thousands	12 Months Ended
	Jul. 31, 2022	Jul. 31, 2021	Jul. 31, 2020
Mineral Property Expenditures	$ 10,154	$ 4,479	$ 4,582
Palangana Mine [Member]
Mineral Property Expenditures	1,060	890	1,343
Burke Hollow Project [Member]
Mineral Property Expenditures	3,647	1,446	1,130
Goliad Project [Member]
Mineral Property Expenditures	240	237	190
Anderson Project [Member]
Mineral Property Expenditures	108	79	71
Workman Creek Project [Member]
Mineral Property Expenditures	33	33	33
Reno Creek Project [Member]
Mineral Property Expenditures	821	672	597
Christensen Ranch Mine [Member]
Mineral Property Expenditures	1,257	0	0
Ludeman Project [Member]
Mineral Property Expenditures	219	0	0
Antelope Project [Member]
Mineral Property Expenditures	70	0	0
Moore Ranch Project [Member]
Mineral Property Expenditures	143	0	0
Barge Project [Member]
Mineral Property Expenditures	37	0	0
Yuty Project [Member]
Mineral Property Expenditures	86	31	66
Oviedo Project [Member]
Mineral Property Expenditures	619	372	350
Alto Parana Titanium Project [Member]
Mineral Property Expenditures	574	199	230
Other Property Acquisitions [Member]
Mineral Property Expenditures	$ 1,240	$ 520	$ 572