Silica Gel Blue semi-transparent glassy substance containing an indicator as “Cobalt Chloride” a heavy metal salt. When free from moisture the Granules or beads are dark blue in color. As the beads takes up moisture, they turns to light blue gradually & When they turn pink, it is mainly used as indicator for the extent of dehumidification and moisture absorption in sealed vessel and Silica Gel Breather Industry. Blue Silica Gel is also know as Indicating Silica Gel, Self Indicating Silica Gel, Blue Desiccants, Moisture absorber.