Note 3 - Inventories - Components of Inventory (Details) - USD ($) $ in Thousands	Jun. 30, 2022	Mar. 31, 2022
Raw materials	$ 2,125	$ 1,490
Work in process	2,244	2,868
Finished goods	5,788	4,595
Supplies	542	513
Inventories	$ 10,699	$ 9,466

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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