Note 3 - Inventories - Components of Inventory (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Mar. 31, 2021
Raw materials	$ 1,399	$ 547
Work in process	3,273	3,206
Finished goods	3,743	4,423
Supplies	309	239
Inventories	$ 8,724	$ 8,415

Carrying amount, net of valuation reserves and adjustments, as of the balance sheet date of merchandise or goods held by the company that are readily available for sale.

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Amount after valuation and LIFO reserves of inventory expected to be sold, or consumed within one year or operating cycle, if longer.

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