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 turn into light pink. This indicates that the gel has absorbed approximately 8% percent of its weight in water. It indicates that the gel needs to be replaced or regenerated. The indicating silica gel will still absorb up to 40% of its weight in water vapor just like the non-indicating. In fact, 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 Self Indicating Silica Gel, Blue Desiccants, Moisture absorber.