Note C - Inventories - Summary of Inventory Values by Product Group (Details) - USD ($)	Jun. 30, 2019	Mar. 31, 2019
Inventories	$ 43,757,046	$ 49,062,086
Prime Coil Inventory [Member]
Raw materials	20,253,958	26,240,439
Non-standard Coil Inventory [Member]
Raw materials	2,431,599	2,078,008
Tubular Inventory [Member]
Raw materials	5,359,827	4,418,750
Finished goods	$ 15,711,662	$ 16,324,889

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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