Note C - Inventories - Summary of Inventory Values by Product Group (Details) - USD ($)	Sep. 30, 2020	Mar. 31, 2020
Inventories	$ 26,499,508	$ 35,668,243
Prime Coil Inventory [Member]
Raw materials	11,619,275	17,190,435
Non-standard Coil Inventory [Member]
Raw materials	933,318	1,550,734
Tubular Inventory [Member]
Raw materials	1,806,531	4,888,542
Finished goods	$ 12,140,384	$ 12,038,532

Amount before valuation and LIFO reserves of completed merchandise or goods expected to be sold within one year or operating cycle, if longer.

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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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