The total mineral content is the total amount of minerals in the soil that may have bound with several soil components like the oxide, organic matter, soil silica, the exchangeable minerals etc. And these minerals can only be determined by sequential extraction. But potential available minerals are those already in solution which are readily available for plant to uptake. In essence, potential available minerals are fractions of the total minerals.

In general, mineral available in 3 forms viz., solution, exchangeable and fixed form. By analytical method, we can estimate mostly solution and to some extent exchangeable one, which constitute available amount. If want include all 3 forms, it constitute total.