Note C - Inventories - Summary of Inventory Values by Product Group (Details) - USD ($)	Dec. 31, 2020	Mar. 31, 2020
Inventories	$ 30,130,320	$ 35,668,243
Prime Coil Inventory [Member]
Raw materials	15,459,864	17,190,435
Non-standard Coil Inventory [Member]
Raw materials	2,178,029	1,550,734
Tubular Inventory [Member]
Raw materials	2,671,140	4,888,542
Finished goods	$ 9,821,287	$ 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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