Orange Color-Variable Silica Gel is non-toxic, odorless and chemically stable. PXZT Silica Gel is a substance used as desiccant, when the beads take up moisture the color will turn tight blue.Appearance:Silica gel, composed of solid micro-porous silica beads, are typically used as adesiccant. The numerous, interlocking pores on the beads work by creating a lower vapor pressure than the ...