THE 2-MINUTE RULE FOR WATERPROOF METAL INDICATOR

The blue color of calmagite at pH =10 is transformed to purple by addition of Mg- ion. The improve being reversible,Calmagite and Eriochrome BlackT (EBT) are these types of indicators that change from blue to pink once they intricate with calcium or magnesium. The endpoint of the complexometric EDTA titration working with either Calmagite or EBT