(1) The percentage of calcium sulfate, expressed as CaSO4•2H2O or CaSO4, if the product is gypsum or plaster or is an agricultural mineral in which calcium sulfate is the principal ingredient.
(2) The percentage of all ingredients contained in the product, in terms prescribed by the State Department of Agriculture, for all other agricultural minerals or mixtures of agricultural minerals with a principal ingredient other than calcium sulfate. [2001 c.914 §7; 2009 c.97 §5; 2015 c.514 §7]