Note 6 - Property, Plant and Equipment (Details Textual)	9 Months Ended
Apr. 30, 2021 USD ($) a
Promissory Note [Member]
Debt Instrument, Face Amount	$ 380,000
Goliad Project [Member]
Area of Land (Acre) \| a	100
Payments to Acquire Land Held-for-use	$ 487,995

Face (par) amount of debt instrument at time of issuance.

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant