This type of blue semi-transparent Silica gel, contains the indicator as 'cobalt'. When free from moisture, the particles are dark blue. As the particles take up moisture, they turn to Light Blue and then to Pink and this indicates saturation and now requires replacement or regeneration.
blue silica gel is ideal as a primary desiccant or blended with other desiccants in any application where visual control of moisture is required. silica gel beads are saturated with a moisture indicating solution that gives them a deep blue color when dry. The color changes from blue to purple to pink as it adsorbs moisture.
