Note 3 - Acquisition of UEX Corporation - Replacement Warrant Assumptions (Details)	Jul. 31, 2024 $ / shares	Jul. 31, 2023 $ / shares	Aug. 19, 2022 $ / shares	Jul. 31, 2022 $ / shares	Jul. 31, 2021 $ / shares
Exercise Price (in dollars per share)	$ 3.29	$ 3.31		$ 1.92	$ 1.9
Replacement Warrants [Member] | Measurement Input, Risk Free Interest Rate [Member]
Derivative, measurement input	0.0542	0.0525
Replacement Warrants [Member] | Measurement Input, Price Volatility [Member]
Derivative, measurement input	0.55	0.6443
Replacement Warrants [Member] | Measurement Input, Expected Term [Member]
Derivative, measurement input	0.1	1.1
Replacement Warrants [Member] | Measurement Input, Expected Dividend Rate [Member]
Derivative, measurement input	0	0
Replacement Warrants [Member] | Minimum [Member]
Exercise Price (in dollars per share)	$ 2.33	$ 2.44
Replacement Warrants [Member] | Maximum [Member]
Exercise Price (in dollars per share)	$ 3.22	$ 3.36
Replacement Warrants [Member] | UEX Acquisition [Member] | Measurement Input, Expected Dividend Rate [Member]
Derivative, measurement input			0
Replacement Warrants [Member] | UEX Acquisition [Member] | Minimum [Member]
Exercise Price (in dollars per share)			$ 1.11
Replacement Warrants [Member] | UEX Acquisition [Member] | Minimum [Member] | Measurement Input, Risk Free Interest Rate [Member]
Derivative, measurement input			3.18
Replacement Warrants [Member] | UEX Acquisition [Member] | Minimum [Member] | Measurement Input, Price Volatility [Member]
Derivative, measurement input			90.98
Replacement Warrants [Member] | UEX Acquisition [Member] | Minimum [Member] | Measurement Input, Expected Term [Member]
Derivative, measurement input			0.75
Replacement Warrants [Member] | UEX Acquisition [Member] | Maximum [Member]
Exercise Price (in dollars per share)			$ 3.42
Replacement Warrants [Member] | UEX Acquisition [Member] | Maximum [Member] | Measurement Input, Risk Free Interest Rate [Member]
Derivative, measurement input			3.23
Replacement Warrants [Member] | UEX Acquisition [Member] | Maximum [Member] | Measurement Input, Price Volatility [Member]
Derivative, measurement input			101.52
Replacement Warrants [Member] | UEX Acquisition [Member] | Maximum [Member] | Measurement Input, Expected Term [Member]
Derivative, measurement input			2.05