9. Income Tax (Details 1) (USD $)	12 Months Ended
	Mar. 31, 2014	Mar. 31, 2013
Income Tax Details 1
Federal tax at statutory rate	$ 1,722,000	$ 708,000
State taxes, net of federal benefit	55,000	18,000
Excess percentage depletion	(678,000)	(415,000)
Changes in state rates and other adjustments to deferred taxes	26,000	(9,000)
Income tax expense	$ 1,125,000	$ 302,000
Effective rate expressed as a percentage of income before income tax	22.20%	14.50%