DRIERITE, Indicating is Calcium Sulfate, Anhydrous. It is impregnated with cobalt chloride making the material blue when dry and changing to rose-red upon absorbtion of moisture. The material is an all-purpose drying agent. As a desiccant, it is capable of absorbing about 6.6% by weight of moisture and 10-14% by weight of moisture in gases.
DRIERITE-Registered Trademark of W.A. Hammond Drierite Company.